Industrial Hygiene for MYLAR PuaiL. " The Mining Industry U.S. Department of Labor William E. Brock, lll Secretary Mine Safety and Health Administration | David A. Zegeer Assistant Secretary Programmed Instruction Workbook No. 12 7321272, PUR HD 54 L552 PREFACE /G86 PUBL This is one of a series of programmed instruction workbooks developed and published by the National Mine Health and Safety Academy. Twelve such workbooks have been developed in the subject areas listed at the back of the book. The format is designed for self-paced, individual study, and the in- formation is primarily for the user who has no experience or training in the subject area. Those who have some experience and knowledge in the subject may cover the basic material at a rapid pace and find the book useful for review. The accident frequency rate for the entry-level miner has, unfortunately, been notably higher than that for the experienced miner. One of the impor- tant objectives of this series of workbooks is to support and complement other training given to entry-level miners and, in this way, to contribute to their safety and health. This publication is for instructional purposes only and is not intended to change or influence existing MSHA policies or directives. This particular volume was prepared initially by an independent contractor and was subse- quently revised, edited, and printed by the U.S. Department of Labor. As it is a new publication in a new format, a Timited initial printing has been made so that content and form can be perfected prior to general distribution. A questionnaire has been provided at the back of the book. Comments are invited from all users. - py por , 0 pp uy oh wry hE a lias Bt k fl = ~ ne Sm SL AESE, ad Ady _ oles hb J g i te, as a8 BN al | i a | a ho 5 ig a 1 ) ® i Ae i = Ah ee il iA a Bs Fe . i Pe 7: a) SET hes 4 oh 2 ay Ry 1] pi A le i 4rd TR FL as a Tg fn gy el ol id “ig - ih Ac did hr oo fog TABLE OF CONTENTS PAGE PREFACE ves ssrerssrrsnsisssisvsnavnsnsunnssnnniossasoessones satnaseinns i INDUSTRIAL HYGIENE AND THE HUMAN BODY (SECTION A) ....viinniiiniinennnnn. 1 INTRODUCTION osc vvvsrriensdibrariesvasasbns ss snvasins somsvsnsssss vo nwenss 3 THE RESPIRATORY SYSTEM i uvvsscosrsnsivssvnsvass vonvenusovissesosines 12 CARDIOVASCULAR SYSTEM iv vcrnirsrnsrvannle snbsssssbiassvnss ssssnisnrmns 24 LIVER FUNCTION suvassmensvnnassusvassnnesapsssevsoses ons vnnney sveves 32 KIDNEYS (ic crnsnsresincnnnsnrnsnves sosinsssnnsrssssssvssnsidessnsssssnins 33 CENTRAL NEPVOUS SYSTEM cu cvusnvrssnnprovnsernomessssamyxoivgs snes sus 38 MUSCULO-SKELE TAL SYSTEM iy vir usinninis's sain draltin s ¥en wn wines drafbncbis #8 + ict wd 5 41 SHIH ne ett mic isnt prs boa n ene se sv sie ss wale od seme snse wa sons ses nse 47 THE. ERR: Laide nnan rasan ves sans eyes creams » danse suym aun sivs shsny « vavhes 51 TBE EYE «sens evmstrng sme bon simu sn sos yiis shin bs ooh sds ae evons sis ono 56 RECOGNITION OF HEALTH HAZARDS (SECTION B) tuuuvruiininiiinnnnanannnns 67 TORICHLOBY ivccavivorunmivivimes names vassensssioks oes suas ensns sos asi 69 ROUTES OF ENTRY yi rvvcussvtnssansmsmannnsresansannrssnssnssbvassstonnn 71 DOSE-RESPONSE RELATIONSHIP iuupuiivrusssmnupissnvibnesvessosaames sos 74 CHEMICAL HAZARDS «vo cv ts mmacvn mmm vu fnnidpn fine nn as o's nvannme oo piso sls voles 81 SOLVENTS co cviomisvnmmmninsrssiss dnmavisone s dsm sass sh snissosssnnes 81 YHOUSTRIAL “SIINDISEASE viv oo willing whine srs u's nw vons platen won sieve nw 4 00 85 BASES scusicivinsigmnmnis nin vhs ope ns kine 5 55 LEE 5800 5 © SE00 5000 na ale ss 90 DUSITS: «vivir sn wns wun ubis nurs vie sn Sunt wm sms mgs na a wn g's 50 swine = nr swigniny s 95 FUMES coin sivilnnnonsnns mane sss os stress idiaass dans «sae 0 ns 20 00 oo bingess ss 101 MISTS: ovale min striae da Suteints wow w dudin mu 0% swam ws iris wand Sone dims sen sidny 104 PHYSICAL HAZARDS «vrs SB hin ns cam so sin ans sot oud wos sums o£ oars ne tn sos 107 NOISE AND: VIBRATION: ott uns cpus nips voimns vie 6.0.0 000s nus obs dnns mn in's vine 108 TEMPERATURE “AND PRESSURE .oneicosisvnssninnsnobnnononinshaonines sno 114 ILLUMINATION AND RADIATION. ..cdvusrnvinnssssrnins sasamases vasmns sos 122 BIOLOGICAL/ERGONOMIC STRESS. « .viviensvrssnsnesasnnensonssonvnssossss ns 129 EVALUATION AND CONTROL OF HEALTH HAZARDS (SECTION C) ..vvevnvevennnnnn. 137 EVALUATION AND MEASUREMENT iyi ix nuis dine es st savin wasn sv nn s sna oh 6610s 138 DIRECT-READING INSTRUMENTS wu visinnmusnnnevaniorsnsswanssnunmniss osvines 144 PREVENTION AND CONFROLY ou cous svintisiona’snnnsnmannsssy sel nsiinss semaine 165 APPLICATION OF CONTROLS: uuu nnrninnesnvasntonnsanessnrkonsssssedbyns 184 TABUSTRIAL HYGIENE AND MINING {SECTION D) suvovsonnissnensonansfannos es 195 RECIBENTS ouinnvlblinsnvnanrsninrnsnrssnssindeisnsness espe souls vues vs 197 THE LBW .. i aictein wimssn oh apmummns sng ss Limi shonin ss oes Roe sivnh won sven ale 199 PINESHAZARDS vives nnn one saninns ob pus b due sian aens soni suv sno sthuiss ss es vs 200 MINE ATMOSPHERE AND BASES .i.vivvssvsarviinsonmssiinmnesssvorsovsneses 201 RADIATION cvs svins wns su natins s dng she sane vrs evs duhmns salir sssins viv sse yes 217 HEAT STRESS wuvetineusvnsviivns es aries opind sins sins hny a sensinasivs ok siivsivns 221 DUST AND -NOTSE '.vuvnins sess vnnndasns ans sins ties snss een sWiesiine vunevios en 223 SKIN DISEASE wis tiv tba suing vu wuinien sien mils wwe dl in wet « 4ihen + £0 w wid imin 440 232 ILLUMINATION-AND. ERGONOMICS ovo sinunpmins cvivnmmine smsnnins sus sins sane 233 OTHER SAFEGUARDS ‘ic cvmn smn saimn nn po wns sities vie sins wins inn spies sdinsws oo so 237 QUESTIONNAIRE... \ «iin soph vs snnivs 120k vhs vrnpleh niin eve sus see uw bnvisienivn +s nies 245 iv FIGURE 1A 2A 3A 4A 5A 6A 7A 8A 9A 10A 11A 12A 1B 2B 3B 4B 5B 6B /B 8B 9B 10B 11B 12B 13B 14B ILLUSTRATIONS PAGE SECTION A RESPIRATORY i SYSTEM cvevencscsscsvrvsnsnsspnsnnsnnsssnshsss vrs 13 AIR SAC 1vrsessisssnstasisnssnnsvonsinssven nesses sinses snes 17 BREATHING CYCLE «vvvuvssssressumevisssanse sony sioiepennmens ssn 18 SYSTEMIC AND PULMONARY PUMPING SYSTEM iver rvsvonesvnnnnanenns 25 THE CIRCULATORY SYSTEM . i. crincisnvosnnpromsnionsns vombsssnonss 26 THE RIDNEY ovis asnnnsas nerssnnsinsnvs 14s maosonssestnsdasstss 33 THE ‘CENTRAL NERVOUS SYSTEM. ..sss cn snan ews vmsnmsns ne nsnnnsnivees 38 MOVEMENT OF THE SPINE 4 iccvovavsmnerionssvsnsmeinsvosnsmassmosys 43 CROSS-SECTION OF THE SKIN ..iiicsnbsbvsnovovivnsssrnnopsspmess 48 STRUCTURE OF THE EAR wavisasversbmunsnsusinsyvbmnnsnvosesoss 52 TLLUSTRATION OF THE EYE ...cocsnconsconsonnsnennssrsnamurnsonss 56 FOREIGN OBJECTS IN THE .-EYE ..coiicanesnrnnennesbrpssdnsnrennanse 58 SECTION B ROUTES OF ENTRY... ivi vivisnadisissen srerssnns snusvosrvonssones 71 DOSE -RESPONSE RELATIONSHIP ..yurisnras rave tans nove sess vias suse 74 SOLVENT LABEL .iciisasssvesvnsvnnnesWunsssnisosmrinns svssnvnss 82 INDUSTRIAL DERMATITIS ON HANDS «cn cssammonins vismemenneysiv's 86 BURN CLASSIFICATIONS .. icin dusvproninvermasssnanrsnnecornsntys 87 GENERAL CARE FOR CHEMICAL BUPMS .cuicisssnsrissavnis innsmponies 88 MAKEUP ‘OF ‘CLEAN, DRY AIR .ucrrsvinuevsrnnenvspssrnn snus crummy 90 SOUND WAVES ..ividichsnscsesdondmnn sn snunhnn anise sn vesrsssnss 108 NOISE LEVELS covnvivneemnnnsrnonnnsssnshnumnn rs enmtyinnsosnr es 109 HEARING DAMAGE “ucviussedaisnnsrsnssn noasnnsgit ssovinntnnssansnes 110 TYPES OF NOISE cuiavinssnnassnvnanin vhenunns ssn es nies sins in 112 ROR OUTPUT ou vununsrsnsmanstdoens su sinssesons ons assumes sss pn sine 114 IN HOT WORK SITES, COOL DRINKING WATER CONTAINING 0.1 PERCENT SALT. SHOULD BE USED ..oowsnisimwniowipio sin sno von # uh ites bimini 118 RADIATION «conn nunmic s pusmesiniy shims sn skein wosmnee sss sass 123 FIGURE 158 16B Nr? Cr? mr? a? at? Na? Sr? tt Nr? a? PAGE HO SMOKING. oi ction ws iit rn nanuls shen 5 mmminee voaialers mis massin sais bia caieihi wo ole 126 LIFTING ov nvv svennmitinvrnsnnsopiss sie suid sos bose sh v odoin somsisns 133 SECTION C PERSONAL "SAMPLER READY FOR USE ...cxusvvsnsnmanevssminsninnesns 141 NOISE SURVEY PROCEDURE . iuunusvis sssunssssosmenosnnoesnssaissie 142 HAND-HELD METHANE "SPOTTER: ..cnvnnswus sessnsion sue snes vines snes 145 MACHINE-MOUNTED METHANE MONITOR \uvuvevvessonnssrmvnnsnessanes 145 HAND-HELD ‘METHANE TESTER... civmevvanssrsminans sis nnress onesies 146 MINER “TESTING FOR METHANE: ,..vvecunnonsssonson sans snips osneons 146 FLAVIE: SAEETY LAMP veh envio vo od non vn shui ier sls die pies wo o's.» mdf 147 OXYGEN INDICATOR suinnsinen vs swss tus sus su vis sinn saw sais 508 rnin 148 BANEMOMETER veils da snmiiini dln sunifins 2 4 win win 4 pares 4 8 ie avin 00 0015 winip wiaid 149 ANEMOMETER AIR MEASUREMENT oy cucvss urns nanwmesysadsione serpin 149 GRAVIMETRIC ‘DUST SAMPLER ‘ov unvvivvsn suis cumsnnnnsonsvnssninss 151 MRE GRAVIMETRIC RESPIRABLE DUST SAMPLER ...........ccvvuinn... 152 SOUND LEVEL METER suvsvenevnninions vnnamnn's & pe vishini renin wean e 153 NOLSE "DOSIMETER. ooo nv vl soins wn wssompwiny sn wwsiom ens vam dom « Su 153 RADIOACTIVE RADON GAS BATTERY-OPERATED, PORTABLE PUMP ........ 155 SLING PSYCHROMETER .uun sv swuwndins wunnsevnion sms nse vrnmmn ovine ss 156 CARBON MOMOXIDE. TESTER “fvur vv inn sidiinsntn sare s sion ss vous an sine snip nse 159 CARBON MONOXIDE LENGTH-OF-STAIN INSTRUMENT ................... 159 PORTABLE LENGTH-OF-STAIN HYDROGEN SULFIDE DETECTOR ........... 160 NITROGEN DIOXIDE DETECTOR ..couv cane snsvnenannsnmnsininsus sive sas 160 DRAEGER MULTI-GAS DETECTOR «ov ivvsvensssnssssnssrossersasasns 161 MOLTT «GAS DETECTOR vv views v sun ntis vin ns win natin bine » winie ss 0isi a 00 i #0 162 USING WATER FOR WETTING DUST cen vevsnnvevonnsnnninnsnnsneresrsns 168 LOCAL EXHAUST VENTILATION. L.iuicucssvnvissssnnninusannvpasnnesiasn 169 EYE AND FACE SHIELDS ....uvvevecvvesvamvivann sesinsen van sa'svass 174 EAR PROTECTION. ..v ovine sruvmsnumpuinimmnioss So wnais sn sain sive suena 175 SUPPLIED-AIR TYPE RESPIRATOR , .cvnvuue sonmen van munsbnasssssnns 178 Vi FIGURE 20C 21C 22C 23C 1D 2D 3D 4D 5D(1) 5D(2) 6D 7D 8D 9D 10D FILTER-TYPE RESPIRATORS iin snnnumnst erraspsin ss snnenn or buenas HOW -A RESPIRATOR WORKS ..vurumiusrsasnrnnnnnsssscoabanes conus PORTABLE SAFETY CAN ..ivasnssmurnsssnsssomesss nyasns sn se onions CORRECT LIFTING uuu sininnnnsn vs thos ss emme memes sme snss shvesssents SECTION D AN OXYGEN-DEFICIENT ATMOSPHERE WITH AN EXCESSIVE AMOUNT OF NITROGEN WILL NOT SUSTAIN LIFE ...ueivuueiniiiiiiiiiiinnnnnn THE SUPPLY OF OXYGEN THROUGH THE LUNGS INCREASES WITH AN INCREASE IN THE CARBON DIOXIDE (CO2) CONCENTRATION ........... EFFECTS OF CARBON MONOXIDE CONCENTRATIONS AND EXPOSURE TIME ON HUMANS ', cituusnu sr osvsen st ns sa Wnu ss mre sitios es sui sve wie LONG-TERM EFFECTS OF CARBON MONOXIDE IN COMBINATION WITH THE HEMOGLOBIN OF THE BLOOD suv es vennsiovssvsmmnenwpmsvin AIRBORNE RADIATION. HAZARD ov vssniunm odin agus ans vn yas sss sppens EQUCATIONY vc. co nnes sus nen desniog oss nes mons sins saatoesmmasn dae ss 2 ay 4 i Al] wal Be Ards ge oul Sas . ol . == yh See = ag, LE : Wit : ; LRA igen Fc HTH id "Hf art rE gabe BE LSE SF TRL ERA © gar Cry ne ) ‘Thames } a . aged Ly patie ix 3 x ) - . - fr pte = tk Cr hy a % oo Y =l.= Eg a hii £0 re 0 LL oT I sd ER INDUSTRIAL HYGIENE FOR THE MINING INDUSTRY SECTION A "INDUSTRIAL HYGIENE AND THE HUMAN BODY" oo os fi “ha pn 2 - i J - he ve i Xu a = EE J £8 = Charger Pi SRI 1 SE co A: ey | ¥ hab : Cg N pe Sc alr # “rl Fondue ds Soros pi Ta! i JE a, ) 3 ple a En, 1 “« i Fi g ea W fog gi r=? 3 REE AL, Bite 4 ne. 0 nat < § ce NE dt Ey a. = IL Tels, Fis Taille 0 hy A de Wa = 22 of . 1A Introduction This course is about industrial hygiene. There are four sections in this particular course, and they must be completed in the order they are presented. The book has been prepared in a programmed instruction format. Some characteristics of programmed instructional material that make it different from normal learning methods are: 1. The subject matter has been broken down into a series of easily-learned, small steps. 2. The student is given frequent opportunities to respond to the important points to be learned. 3. The student can immediately check his or her response to see if itis correct. This method of providing written instruction was developed in the 1950's to answer the need to simplify the learning process and make it useful for self-paced, individual study. The use of programmed instructional materials has proven to be an effec- tive alternative to textbooks if the student responds to the questions and then checks the answer immediately. Each subsection (paragraph or paragraphs between the lines) is called a frame. Each frame has a number and a letter located in the upper right-hand corner. This frame is number 1A which means it is the first frame in Section A. 2A As you work through this course, you will frequently be asked questions relating to the material that has been covered. The questions will be either true/false, multiple choice, matching, or fill-in-the-blank. Think carefully about each question and then record the best answer. The correct answer to the question will be given immediately following the question within the same frame, or, in the case of a review exercise, following the series of review questions. 2A WHERE WOULD AN ANSWER BE GIVEN TO A QUESTION ABOUT THIS FRAME? (CIRCLE THE CORRECT ANSWER) A. AT THE END OF SECTION A B. IN THE NEXT FRAME C. ON A DIFFERENT PAGE D. FOLLOWING THE QUESTION AND IN THE SAME FRAME 3A The purpose of this course is to introduce industrial hygiene, which deals with the recognition, measurement, evaluation, and control of various health hazards associated with modern industry, particularly, the mining industry. In order to learn as much as possible, always write your answers to the questions asked before looking at the correct answer. Remember, your knowledge and personal responsibility are the important keys to your good health. TRUE OR FALSE IF YOU ARE UNSURE OF THE CORRECT RESPONSE, CHECK THE CORRECT ANSWER AT THE END OF THE SECTION. Answer: false 4A In order to better understand the effects of industrial health hazards, Section A of this course, "Industrial Hygiene and the Human Body," will de- fine industrial hygiene and will also show the relationships between indus- trial hygiene and important functions of the human body. TRUE OR FALSE IN SECTION A, INDUSTRIAL HYGIENE WILL BE DEFINED WITHOUT SHOWING ANY RELA- TIONSHIPS TO THE FUNCTIONS OF THE HUMAN BODY. 5A Industrial Hygiene What is industrial hygiene? Industrial hygiene is concerned with the health hazards or stresses present in a work environment and their effects on a worker's health. Health in this sense applies to complete physical, mental, and social well-being, not just the absence of disease. Health hazards or stresses can affect an individual immediately or slowly over a long period of time. Within the mining industry these health hazards can lead to skin, ear, eye, or lung problems for the worker. 6A Specifically, industrial hygiene is concerned with the recognition, evaluation, and control of health hazards existing in the workplace. These hazards or stresses may cause sickness, impaired health and well-being, or significant discomfort and inefficiency among workers or among citizens of the community. FILL IN THE BLANKS INDUSTRIAL HYGIENE DEALS WITH THE CONTROL OF HAZARDS. INDUSTRIAL HYGIENE IS ALSO CONCERNED WITH THE ’ » AND OF THESE HAZARDS. an mm mn em me an ee Answers: health; recognition, evaluation, and control 7A Stress is defined as a chemical, physical, or emotional factor in the environment causing mental or physical tension and possibly disease or fatigue. What then are these environmental stresses? Well, they are grouped in four categories: chemical, physical, ergonomic, and biological. Each of these categories is examined in the frames that follow. FILL IN THE BLANKS ENVIRONMENTAL STRESS FACTORS ARE CLASSIFIED AS ” ’ ERGONCMIC, AND ‘ Answers: chemical, physical, biological 8A Chemical stress usually exists when chemical substances in the air enter the lungs with the air we breathe (inhalation), or when chemical substances enter the body upon contact with the skin (absorption). Such hazardous chemical substances can also enter the body with food contaminated by a worker's dirty hands (ingestion). However, inhalation is the most critical due to the speed a chemical substance taken into the body in this way can be absorbed in the lungs, pass into the blood stream, and reach the brain and other organs. FILL IN THE BLANKS THE MOST CRITICAL WAY A SUBSTANCE ENTERS THE BODY IS BY ... AOTHER WAYS ARE THROUGH AND ‘ Answers: inhalation; absorption, ingestion 9A Chemical substances in the air exist in many forms. Here are some defi- nitions of those various forms. vapors - the gaseous form of substances that are normally solids or liquids (solvent vapors). gases - fluids with no shape that occupy space and can only be changed to a solid or liquid by increased pressure, reduced temperature, or both (methane). dusts - fine solid particles produced by industrial processes such as handling, crushing, grinding, or blasting (coal dust). fumes - fine solid particles suspended in the air as a result of heating metals (welding fumes). mists - fine liquid particles in the air resulting from con- densation and produced when liquids are sprayed, bubbled, splashed, or foamed (cutting oil). smoke - fine particles that occur as the result of incomplete burning. aerosols - any fine liquid or solid particles small enough to remain in the air for a period of time. 9A CIRCLE THE CORRECT ANSWER VAPORS, GASES, SMOKE, AND FUMES ARE EXAMPLE OF A. CHEMICAL HEALTH HAZARD B. ERGONOMIC HEALTH HAZARD C. PHYSICAL HEALTH HAZARD D. BIOLOGICAL HEALTH HAZARD E. NONE OF THE ABOVE Answer: A 10A When these chemical substances have harmful effects on the human body, they are said to be toxic. Some substances are more toxic than others. Chemicals are the most common environmental health hazard; therefore, an awareness of chemical toxicity can protect your health. FILL IN THE BLANK CHEMICAL SUBSTANCES THAT CAN HARM THE HUMAN BODY ARE CALLED SUB- STANCES. Answer: toxic 11A Physical stress, the second category of environmental stress, results from exposure to various extremes of pressure and temperature, mechanical vibration, radiation, and noise. Both chemical and physical stresses can be in various mining operations. As a result, they can produce harmful effects that can have an immediate or a long-term effect on the health of the worker. 11A CIRCLE THE CORRECT ANSWER TWO TYPES OF PHYSICAL STRESSES ARE: A. FUMES, NOISE wo TEMPERATURE, GAS C. FATIGUE, RADIATION D. NOISE, VIBRATION Answer: D 12A Ergonomic stress, the third stress category, pertains to human factors associated with the physical and mental demands of a particular job. Many of these stress factors are internal; they arise from within the worker in response to the individual's perceptions of a particular task. For example, fatigue may result when a worker is required to perform his or her duties in an uncomfortable or awkward position while working with coal mining equipment. Boredom or monotony may affect a worker's per- formance when the assigned task is highly repetitive. When workers worry about personal or job-related problems, their effectiveness on the job will probably suffer. Real or perceived pressure (from an employer, peer group, etc.) can also produce harmful effects. These and other ergonomic stress factors can threaten your health and safety. FILL IN THE BLANK WORRY, FATIGUE, AND BOREDOM ARE EXAMPLES OF STRESS. Answer: ergonomic 13A Thus far, three types of stresses have been discussed, chemical, physical, and ergonomic. The final stress category, biological stress, con- sists of stresses that are not found as often as others in the mining industry Included as examples of things that cause biological stresses are fungi, bacteria, viruses, insects, rodents, and snakes. FILL IN THE BLANK FUNGI, VIRUSES, AND BACTERIA, ALTHOUGH NOT OCCURRING OFTEN IN THE MINING INDUSTRY, ARE EXAMPLES OF THINGS THAT CAUSE STRESS. Answer: biological 14A A worker in a mining operation is exposed to certain occupational diseases and hazards, as is any other worker in industry. It is, therefore, important to obtain a basic knowledge of industrial hygiene principles. In addition, it is important for individuals to take personal responsibility for their health. Management cannot do the job alone. If action is taken to eliminate health hazards, resulting safety hazards will automatically be eliminated too! For example, if noise levels are reduced, ease of communi- cation would increase, thus reducing the possibility of accidents due to poor communication. CIRCLE THE LETTER OF THE MOST CORRECT ANSWER IT IS IMPORTANT TO HAVE A BASIC UNDERSTANDING OF INDUSTRIAL HYGIENE BECAUSE AS A WORKER IN A MINE, YOU WILL BE EXPOSED TO: A. DUST B. NOISE C. REPETITIVE MOTION D. GASES E. ALL OF THE ABOVE Answer: E 15A As a means of review, the following chart might be helpful. STRESS FACTORS CAUSING HEALTH PROBLEMS CHEMICAL PHYSICAL ERGONOMIC BIOLOGICAL dusts radiation body position in insects fumes noise relation to task rodents mists vibration monotony snakes vapors temperature boredom fungi gases pressure repetitive motion bacteria aerosols worry viruses smoke work pressure fatigue 16A Many of the stresses affecting miners have been mentioned. These stresses and other hazards can have a definite effect on a miner's continued health and well-being. Exposure to many of these stresses may produce imme- diate (acute) effects on the body or delayed (chronic) effects over longer periods of time. As stated previously, a program of industrial hygiene should consist of recognition and awareness of the health hazard, measurement and evaluation of the hazard, and control of the hazard. In addition, infor- mation concerning the possible hazards present in a work operation and pro- cess, provided in the form of education and training, should be available. FILL IN THE BLANKS STRESSES THAT PRODUCE AN IMMEDIATE EFFECT ON THE BODY ARE TERMED ’ WHILE THOSE PRODUCING A DELAYED EFFECT ARE CALLED . a mS Se eS a Answer: acute, chronic 10 17A REVIEW LET'S PAUSE AND REVIEW WHAT HAS BEEN COVERED TO THIS POINT SO YOU CAN EVALUATE YOUR PROGRESS. 1. INDUSTRIAL HYGIENE IS CONCERNED WITH THE » EVALUATION, AND OF HAZARDS. 2. WHICH OF THE FOLLOWING FOUR CATEGORIES OF STRESS CAUSES THE LEAST PROBLEM FOR MINERS? A. ERGONOMIC B. CHEMICAL C. BIOLOGICAL D. PHYSICAL 3. THE MAJORITY OF ALL ENVIRONMENTAL HEALTH HAZARDS INVOLVE WHICH FACTORS? A. ERGONOMIC B. CHEMICAL C. BIOLOGICAL D. PHYSICAL 4. NOISE AND RADIATION ARE EXAMPLES OF A. ERGONOMIC STRESS B. CHEMICAL STRESS C. BIOLOGICAL STRESS D. PHYSICAL STRESS 5. THE INTERACTION BETWEEN THE WORKER AND THE EQUIPMENT ON THE JOB WOULD BE AN EXAMPLE OF WHAT TYPE OF RELATIONSHIP? ERGONOMIC CHEMICAL BIOLOGICAL PHYSICAL OO OO Ww > 17A Answers: 1. recognition, control, health 2. £ 3. B 4, D 5. A If the correct answers were not clear, review before moving ahead. 18A The Respiratory System In order to understand the effects of industrial health hazards, it is necessary to know how certain parts of the body work, and what effect these health hazards have on the different organs and systems of the body. The respiratory system is one of the most important routes of entry for harmful or toxic substances. Many occupational diseases result directly from the continued presence of toxic chemicals in the respiratory system. Other diseases are caused by passage of harmful substances through the lungs to the remainder of the body with the aid of the circulatory system and the blood. The respiratory system brings oxygen into the body and then transfers it to the blood. The lungs also remove carbon dioxide from the blood and trans- fer it to the exhaled air. CIRCLE THE CORRECT ANSWER THE PRIMARY PURPOSE OF THE RESPIRATORY SYSTEM IS TO A. ALLOW OXYGEN TO ENTER THE BODY B. TRANSFER OXYGEN TO THE BLOOD C. REMOVE CARBON DIOXIDE WASTE D. ALL THE ABOVE Answer: D 12 19A The respiratory system is composed of the nose, mouth, upper throat, larynx or voice box, trachea or windpipe, lungs, bronchi, diaphragm, and chest muscles. The respiratory system can further be divided into two areas. The first is the upper respiratory system, consisting of the airways - nose, throat, trachea, and the major air passages (bronchi) leading to the lungs. The second is the air sacs (alveoli) where the oxygen and carbon dioxide transfer takes place (see Figure 1A). ; Upper throat NOBE rm Mouth —— ; ye Air-conducting tubes: \ Windpipe (trachea) Larynx a. ERY; 3 Major bronchus Medium and small-sized ‘bronchi Chest muscles Alr sacs (alveoll) Bronchiole Scarred air sac and Diaphragm bronchiole (puimona fibrosis) y y Normal air sac Alr sac and with emphysema FIGURE 1A. RESPIRATORY SYSTEM 13 20A The respiratory system is a network of tubes so efficient that a person at rest, inhaling and exhaling about 15 times per minute, gets inhaled air to all parts of the lungs within two seconds. This network of tubes divides many times from one tube, the trachea (windpipe), to smaller and smaller tubes that end at the alveoli where the transfer of oxygen and carbon dioxide actually occurs. CIRCLE THE CORRECT ANSWER THE RESPIRATORY SYSTEM CAN SPECIFICALLY BE DIVIDED INTO TWO AREAS. A. NOSE AND LUNGS B. AIRWAYS AND BRONCHI C. AIR SACS AND AIRWAYS D. THE ALVEOLI AND AIR SACS E. BOTH C AND D ABOVE Answer: C 21A The nose, throat, windpipe (or trachea), and bronchi (smaller air tubes which branch out from the windpipe) make up the airways of the upper respira- tory tract through which air must travel on the way to the air sacs in the lungs. Air which is breathed in must be filtered and humidified before reaching the alveoli in order to avoid injury to these delicate air sacs. The first step in this process is performed by the large hairs and moist mucous membranes of the nose. FILL IN THE BLANKS FILTERING AND HUMIDIFYING THE AIR BREATHED IN IS DONE BY THE LARGE AND MEMBRANES OF THE NOSE. Answer: hairs, mucous 22A In addition, there are other natural defenses in the upper respiratory system. The windpipe and bronchi have a 1ining of microscopic hairs called 14 22A cilia. There is also a coating of mucus produced by cells in the windpipe, bronchi, and bronchioles (tubes even smaller in size than the bronchi) that help trap dusts and other foreign particles. The purpose of the cilia is to act as a tiny conveyor system to move particles that have attached to the mucus up the respiratory tract to be expelled by the mouth or nose. This is referred to as the pulmonary escalation system. These bronchioles are also provided with tiny muscles which can close altogether in order to prevent air from reaching the air sacs. This happens when an individual is exposed, for example, to an extremely irritating gas, like sulphur dioxide. In effect, your body automatically refuses to breathe in the gas, and you hurry from the area of contaminated air, gasping for breath. CIRCLE THE CORRECT ANSWER THE BODY CAN ACTUALLY REFUSE TO BREATHE AN EXTREMELY IRRITATING GAS WHEN A. MICROSCOPIC HAIRS, CALLED CILIA, MOVE PARTICLES UP THE RESPIRATORY TRACT. B. TINY MUSCLES OF THE BRONCHIOLES CLOSE OFF THE RESPIRATORY PASSAGE TO THE AIR SACS. C. LARGE HAIRS BECOME COVERED WITH MOIST MUCUS. D. COUGHING, CHOKING, AND SNEEZING BEGIN. Answer: B 23A The last two frames have dealt with the natural defenses available in the upper respiratory system. In addition to those already mentioned, two very common protective defenses have not yet been discussed - coughing and sneezing. Everyone coughs and sneezes, and this reaction also tends to get rid of irritants in the upper respiratory tract. These are defense mechanisms often forgotten. FILL IN THE BLANKS FIVE NATURAL DEFENSES IN THE UPPER RESPIRATORY SYSTEM ARE : » TINY MUSCLES, » AND ‘ Answer: sneezing, coughing, mucus, hair or cilia 15 24A Only particles of a certain size can even enter the lungs during breath- ing. The size of such particles is measured in terms of microns. One micron is 1/25,000 of an inch. For example, particles below 40 microns in size can- not be seen by the human eye. Although some particles 10 microns and smaller can enter the lungs, nearly all larger particles are trapped by the natural defenses of the nose, throat, larynx, trachea, or bronchi. Here they are swallowed or removed from the body by way of the mouth or nose. FILL IN THE BLANKS BECAUSE THE SIZE OF PARTICLES THAT CAN ENTER THE RESPIRATORY SYSTEM AND LUNGS ARE SMALL, THEY ARE MEASURED IN . MOST LARGER PARTICLES ARE REMOVED BY THE OF THE UPPER RESPIRATORY SYSTEM. Answer: microns; natural defenses 25A To this point, we have examined the upper respiratory system. Let's turn attention now to the business district of the lungs, the air sacs. In the lungs there are millions of tiny air sacs surrounded by blood. The air in these sacs is separated from the blood by a membrane so thin that gases can readily pass back and forth through it. There are two gases that are constantly being exchanged through these membranes: oxygen is passing from the air in the sacs into the blood, while carbon dioxide from the blood passes into the sac. Look at Figure 2A to get a better idea of what is happening. 16 25A Carbon dioxide Oxygen Membrane Blood FIGURE 2A. AIR SAC FILL IN THE BLANKS THE MEMBRANE WALL OF THE AIR SAC IS SURROUNDED BY WHICH IS ESSENTIAL IN THE PROCESS OF EXCHANGE. a = nn A Answer: blood, gas 17 26A Every time a breath is taken, air goes all the way down to the air sacs in the lungs. The oxygen then passes through the membrane wall of the air sac into the blood which surrounds it. The carbon dioxide, which is the waste gas given off by bodily processes, is carried by the blood to the lungs where it passes through the membrane to enter the air sac. When you exhale, this carbon dioxide is ejected from the air sac to make room for more needed oxygen. This is how the breathing process works. Remem- ber, a complete inhale-exhale cycle takes only a few seconds. CARBON DIOXIDE Inhalation Exhalation FIGURE 3A. BREATHING CYCLE FILL IN THE BLANKS THE EXCHANGE OF GASES IN THE LUNGS TAKES PLACE THROUGH THE MEMBRANE WALLS OF THE . WHEN YOU BREATHE, ENTERS THE BLOODSTREAM THROUGH THE AIR SACS, AND A WASTE GAS, ENTERS THE AIR SACS READY FOR REMOVAL WHEN YOU EXHALE. Sm Answer: air sacs; oxygen, carbon dioxide 18 27A In order for particles to enter the air sacs within the lungs, particles must usually be smaller than five microns in size. These particles are re- ferred to as respirable. However, only particles smaller than % micron are likely to enter the air sacs. This is the area where the lungs are most likely to receive damage. 28A The air sacs have two main defenses against these small particles. The lining of the air sacs is covered with a fluid-1ike substance for protection. Although this fluid is unlike the mucous lining of the upper respiratory airways, it accomplishes the same cleansing function. The second defense is provided by phagocyte cells, which are white blood cells that are able to surround and contain particles of this size. FILL IN THE BLANKS THE AIR SACS HAVE TWO MAIN DEFENSES, AND TO PROTECT THE LUNGS AGAINST PARTICLES SMALLER THAN FIVE MICRONS WHICH ARE TERMED Answer: fluid, phagocyte cells, respirable 29A The sense of smell is also important to the respiratory system. There are cells Tocated in the nose that are sensitive to odor. Since air must pass these odor-sensitive cells Tong before it reaches the air sacs located in the lungs, the body has a chance to detect a harmful substance. The reflex action of the body to stop breathing is its way of trying to protect the lungs. However, this defense is limited by the fact that these odor sensi- tive cells can lose their ability to detect any odor to which they have become accustomed. The term for this loss of smell is olfactory fatigue. It is for this reason that the sense of smell cannot be depended upon as a warning system in the working environment where unpleasant and irritating odors may be a normal part of the air in the atmosphere. FILL IN THE BLANKS AN INDIVIDUAL'S SENSE OF CAN PLAY AN IMPORTANT PART IN PREVENTING HARMFUL SUBSTANCES FROM ENTERING THE LUNGS UNLESS THE INDIVIDUAL HAS A CON- DITION TERMED ‘ Answer: smell, olfactory fatigue 19 30A With the assistance of all these defense mechanisms, a healthy lung should be able to clean itself. However, if a substance is not removed from the air sac by any of the defense mechanisms that have been discussed, then a deposit may form in the air sac. Such deposits may or may not affect the lung. If, however, injury to the lung does occur, the degree and form of damage to the lung depends on the type of contaminant, its amount, and the period of a person's exposure. Also, to make the job of self cleaning the lung more difficult, all the defense mechanisms that have been discussed are subject to deterioration and slowing down with age or bad health. Therefore, an older worker's lungs will not be able to cleanse themselves as fast or as well as those of a younger, healthier worker. FILL IN THE BLANKS THE PROTECTIVE EFFECT PROVIDED BY DEFENSE MECHANISMS IS REDUCED AND SLOWED DOWN BY AND ‘ Answer: age, bad health 31A The most common forms of lung disease in this country are cancer, pneumonia, chronic bronchitis, and emphysema. In addition, coal workers’ pneumoconiosis and silicosis are diseases common among miners. These diseases result from respirable dust retained in the lungs. These various diseases are the end result of a long series of small injuries to the lungs. 32A Chemicals that irritate the large and medium-sized tubes which conduct air to the lungs can be found in the environment. Each time these air tubes are irritated, mucus production is increased in an effort to dissolve, dilute, and remove the irritating substances. Due to this increased amount of mucus, an individual will develop a continuing cough trying to remove the mucus now present in the airways. This condition is called chronic bronchitis. 20 32A FILL IN THE BLANKS A CONTINUING COUGH CAUSED BY AN INDIVIDUAL'S TRYING TO GET RID OF INCREASED MUCUS IN THE AIRWAYS RESULTS IN A CONDITION CALLED ‘ Answer: chronic bronchitis 33A If such Tung irritations are present day after day, the glands in the air tubes which produce mucus will increase their production regularly, even when the irritant is not present. Infections thrive in excess mucus. It is for this reason that irritation over a long period can easily lead to in- creased respiratory infections. From that point on it becomes a never-ending cycle: infections lead to more mucus production, and the mucus harbors bac- teria which cause more infections. It is believed that repeated infections damage the small air tubes and probably the air sacs as well. COMPLETE THE FOLLOWING SENTENCE CHRONIC IRRITATION CAN EASILY LEAD TO INCREASED SUSCEPTIBILITY TO INFECTIONS BECAUSE ‘ Answer: infections thrive in excess mucus 34A Emphysema is the serious disease which results when the delicate air sac walls are destroyed. Increased air pressure damaging the air sacs results in a breathing blockage when the air tubes fill with mucus. A breathing block- age can also be caused by direct pressure applied to the smaller tubes by their encircling muscles. This is what happens in asthmatic attacks. As a result, the air, which now cannot be exhaled, becomes trapped. This causes the blocked and narrow tubes to stretch and eventually break. As a result, large empty spaces, serving no purpose, develop in the lungs. These spaces cannot receive fresh air containing oxygen, nor can they discharge carbon dioxide. These parts of the lung, therefore, no longer function. FILL IN THE BLANK THE SERIOUS DISEASE WHICH RESULTS WHEN THE DELICATE AIR-SAC WALLS ARE DES- TROYED THROUGH INFECTION OR INCREASED AIR PRESSURE IS Answer: emphysema 21 35A A condition that results from the air sacs filling with fluids is termed pulmonary edema. This fluid is produced in the lungs in a similar way that a blister forms in response to a burn. As a result of the air sacs being filled with fluid, they are not of much use in the transfer of oxygen. The lungs thus fill with liquids so an individual cannot breathe. Pneumonia is an example of a condition of this type. FILL IN THE BLANKS WITH AN INFECTION OF THE LUNGS CALLED PNEUMONIA, THE AIR SACS FILL WITH WHICH EVENTUALLY STOPS THE TRANSFER OF . Answer: fluid, oxygen 36A Cancer is perhaps the disease that is feared most. A particular type, lung cancer, has been occurring more frequently during the last 10 years. Cells can change as a result of irritation or other factors. If this change is of a harmful kind, cancer will develop. When cancer cells grow, they in- terrupt the growth of normal cells and once this growth begins, it is hard to stop. Any substance that has been shown to cause cancer is called a carcinogen. 37A However, some substances seem to have to be combined with others before they can cause cancer. Cigarette smoke is one of these substances and appar- ently is the largest single factor contributing to Tung cancer. Cigarette smoke may or may not be a direct cause of cancer, but when it is combined with certain substances found in polluted air, a cancer-causing substance exists. This seems to be the case with uranium miners who smoke. In fact, few nonsmoking uranium miners have lung cancer. Other factors contributing to lung cancer may include air pollution from engines, industrial fumes, and specific materials such as asbestos and radioactive particles. FILL IN THE BLANKS A CAUSES CANCER AND APPARENTLY IS THE LARGEST SINGLE FACTOR CONTRIBUTING TO LUNG CANCER. Answer: carcinogen, cigarette smoke 22 38A Another form of chronic Tung disease is pulmonary fibrosis. The term pulmonary fibrosis means lung scarring. Although not common among the general population, it does occur frequently among groups of people who are exposed to certain dusts and chemicals. Pneumoconiosis results from the inhalation of dust and the reaction to the dust. With this in mind, it is obvious that everyone, no matter what his or her occupation, will have some degree of pneumoconiosis. 39A Silica dust causes a typical example of lung scarring called silicosis. Lungs in this condition are not able to destroy or remove collected silica dust. The lung's reaction, therefore, is to produce a large amount of scar tissue. This process is called fibrosis and will eventually cause disability. The scar tissue is located mainly in the walls of the air sacs, causing a de- crease in the oxygen content of the blood. Without a good supply of oxygen, the organs of the body cannot work properly. Silicosis is found among hard coal miners and, to some extent, among soft coal miners, But it also can be found among those who dig for copper, lead, zinc, silver, gold, and those who work at surface sand and gravel operations. It is_also found among those who cut granite out of mountains. FILL IN THE BLANKS A SPECIFIC TYPE OF LUNG SCARRING OR : CAUSED BY SILICA DUST IS CALLED ‘ Answer: pulmonary fibrosis, silicosis 40A Breathing coal dust over a long period of time can cause another form of Tung scarring and disability known as Coal Workers'Pneumoconiosis (CWP or “Black Lung"). In coal mining, increased exposure to coal dust year after year will increase the amount of pneumoconiosis in an individual's lungs. In this situation, the lungs actually harden, becoming nonfunctional, as a result of dust inhalation. In fact, it is believed that there may be as many as 125,000 individuals with Coal Workers'Pneumoconiosis in the United States. FILL IN THE BLANKS BREATHING COAL DUST OVER THE YEARS CAN CAUSE A FORM OF LUNG SCARRING CALLED Answer: Coal Workers' Pneumoconiosis 23 41A One other type of lung scarring results from breathing in asbestos fibers that have escaped into the air, specifically in areas where individ- uals are working with the substance. The disease that results, asbestosis, can result from either long- or short-term exposure. The seriousness of the problem is obvious considering that there are some 200,000 industry workers associated with asbestos products and fibers. The exposure that results is believed to be responsible for 2,000 deaths each year from either asbestosis or cancer. Also, it is important to note that the risk of developing lung cancer is much greater for asbestos workers who smoke. FILL IN THE BLANKS INHALATION OF ASBESTOS FIBERS CAUSES A LUNG SCARRING DISEASE CALLED THREE TYPES OF PULMONARY FIBROSIS OR LUNG SCARRING ARE AND BECAUSE THEY "ARE CAUSED BY DUST INHALATION, THEY ARE ALL TYPES OF Answer: asbestosis; silicosis, coal workers pneumoconiosis, asbestosis; pneumoconiosis 42A Over the years, repeated exposure to irritating substances affecting the lungs creates what is known as a cumulative effect on an individual. Cumula- tive effect simply means that each harmful exposure adds to the effect of the previous exposure. Such an effect will eventually take its toll so that in the final stages the lungs will be unable to supply enough oxygen or remove carbon dioxide from the body. As a result, other organs of the body, such as the heart, will not be able to function normally. FILL IN THE BLANKS WHEN EACH HARMFUL EXPOSURE ADDS TO THE EFFECT OF THE PREVIOUS EXPOSURE, A IS SAID TO OCCUR. Answer: cumulative effect 43A Cardiovascular System Now that we've spent some time oii the respiratory system, let's look at the heart and blood vessels or the cardiovascular system. 24 43A The heart pumps blood to all parts of the body in two pumping systems: one from the right side of the heart (pulmonary) and one from the left side (systemic). All of the blood pumped from the right side of the heart goes to the Tungs where it deposits the carbon dioxide that it has picked up from the tissues and receives a new supply of oxygen. The blood then travels to the left side of the heart where it is pumped to the rest of the body. As shown in Figure 4A, the blood first is pumped through the pulmonary system, and then through the systemic pumping system. This alternation between the two systems is continuous. - Brain ’ x Systemic SL .o Pulmonary FIGURE 4A. SYSTEMIC AND PULMONARY PUMPING SYSTEMS FILL IN THE BLANKS THE CARDIOVASCULAR SYSTEM PUMPS BLOOD TO THE BODY THROUGH THE PUMPING SYSTEM OR RIGHT SIDE OF THE HEART AND THE PGMPING SYS- TEM OR LEFT SIDE OF THE HEART. Answer: pulmonary, systemic 25 44A The blood vessels are a series of branching tubes that carry blood throughout the body. Arteries carry blood with oxygen from the lungs to the cells of the body and the veins carry blood back to the heart and lungs. The thin walls of the smallest bTood vessels, the capillaries, allow substances such as oxygen to be exchanged from the blood to the body tissues, and waste products to be returned to the lungs and kidneys for removal from the body. A buildup of waste products, lack of oxygen, or heat can cause these blood vessels to get larger or dilate. Narrowing or constriction of these same vessels can be caused by such things as noise, nicotine from cigarettes, or cold temperatures. As a result, more blood would flow through a dilated rather than through a constricted blood vessel. Artery Lung Heart Vein Capillaries Kidney FIGURE 5A. THE CIRCULATORY SYSTEM WHICH OF THE FOLLOWING CAUSE DILATION OF THE BLOOD VESSELS? A. SMOKING B. NOISE C. LACK OF OXYGEN D. WORKING IN EXTREME COLD TEMPERATURES 26 45A The heart is nothing more than a muscle. Its job is to beat (contract rhythmically) 60 to 100 times a minute pumping blood through all the blood vessels in the body keeping the body alive. In order to do this job, the heart needs a constant supply of oxygen and in order to deliver the oxygen to the body, the heart can never stop pumping. Therefore, the working rela- tionship between the heart and lungs is very important. Together they form the cardio-pulmonary system. FILL IN THE BLANKS IN ORDER TO DO ITS JOB, THE HEART NORMALLY BEATS TIMES PER MINUTE AND, WITH THE LUNGS, FORMS THE SYSTEM. Answer: 60-100, cardio-pulmonary 46A Blood is a solution which contains substances used by the body as well as waste that the body eventually eliminates. In addition to carrying oxygen and carbon dioxide waste, the blood also has the duty of passing through the digestive system where it picks up digested food and takes it to the cells of the body. It then passes through the kidneys, which filter out waste products. The blood contains white blood cells which fight infection and red blood cells which carry oxygen, as well as platelets that begin the blood-clotting process. The red blood cells also contain hemoglobin, which has the ability to gather large quantities of oxygen from the air in the lungs, carry it to the other parts of the body, and deposit it where needed. The blood's job of transporting oxygen throughout the body is very important. The organs of the body, particularly the brain, heart, and kidneys, cannot survive and function when they are not supplied with oxygen. FILL IN THE BLANKS IN ADDITION TO CARRYING OXYGEN AND ELIMINATING WASTE, THE BLOOD CONTAINS BLOOD CELLS THAT FIGHT INFECTION AND THAT AID IN THE BLOOD CLOTTING PROCESS. HEMOGLOBIN IS RESPONSIBLE FOR CARRYING AND IS FOUND IN THE BLOOD CELLS. Answer: white, platelets; oxygen, red 27 47h Blood vessels, also, can be damaged if they do not get oxygen. For example, this occurs when a person inhales cigarette smoke. The carbon mon- oxide found in the smoke becomes firmly attached to the hemoglobin making it unable to carry oxygen. This occurs because carbon monoxide attaches to hemoglobin 300 times faster than oxygen does. If a high concentration of carbon monoxide happens to be present in the working environment of a mine, a great amount of an individual's hemoglobin could possibly become bound to it, making the blood unavailable for carrying any oxygen. The body then becomes starved for oxygen. If the condition lasts for more than a few minutes, the person may die. In reality, carbon monoxide poisoning could actually be called hemoglobin poisoning. FILL IN THE BLANKS HEMOGLOBIN ABSORBS 300 TIMES FASTER THAN OXYGEN AND LACK OF MAY LEAD TO DEATH. CARBON MONOXIDE POISONING MIGHT ACTU- ALLY BE THOUGHT OF AS BECAUSE IS UNABLE TO CARRY OXYGEN IN THE PRESENCE OF THIS GAS. Answer: carbon monoxide, oxygen; hemoglobin poisoning, hemoglobin 48A Certain chemicals can damage the red blood cell and cause the cell to rupture. When the cell ruptures, large amounts of hemoglobin are released into the bloodstream, which possibly can cause damage to the kidneys. Depending on the chemical cause and the level of exposure, the red blood cells may rupture either slowly or rapidly. When these cells rupture slowly, the symptoms are like those of anemia caused by a deficiency in the oxygen- carrying material in the blood: weakness, fatigue, dizziness, headache, and a pale complexion. Sometimes the victim's skin will also display a yellowish color (jaundice). When the red blood cells rupture rapidly, the victim develops severe anemia. This may leave an insufficient number of red blood cells to carry oxygen to the brain, heart, and kidneys. Lack of oxygen to these organs may then complicate the illness and may be fatal. FILL IN THE BLANKS A RUPTURE OF THE RED BLOOD CELLS FROM EXPOSURE TO DANGEROUS LEVELS OF CERTAIN CHEMICALS CAUSES THE BODY TO LOSE » RESULTING IN ‘ Answer: oxygen, anemia 28 49A Bone marrow, the soft material that fills the inside of the bone, pro- duces a constant supply of red blood cells, white blood cells, and platelets. This bone marrow can be damaged by chemicals or by exposure to X-rays or a harmful kind of radiation such as ionizing radiation used in nuclear gauges found at preparation plants. If the bone marrow is damaged, it is unable to produce a sufficient supply of blood cells. This can result in severe anemia due to the lack of red blood cells, recurrence of serious infections due to the lack of white blood cells, and uncontrollable bleeding due to the Tack of platelets. FILL IN THE BLANKS RED BLOOD CELLS, WHITE BLOOD CELLS, AND PLATELETS ARE PRODUCED IN THE Answer: bone marrow 50A Another problem related to the circulatory system is heart attack. Diseases of the heart are the number one cause of death in the United States. A common cause of heart attack is hardening of the arteries of the heart (coronary arteriosclerosis). Over a period of 20 to 30 years, patches called plaques containing cholesterol (a type of fat found in food and also produced by the body) begin to Tine the small blood vessels which supply the heart with blood. The arteries become stiff and more narrow leading to total blockage over a period of time. When completely blocked, the arteries can no longer supply oxygen to certain parts of the heart, causing damage or com- plete destruction to that part. When this happens, a heart attack occurs. It depends, however, on how much of the heart is damaged or destroyed as to how well the rest of the heart can get along with the loss. 51A A diet that contains a lot of animal fat, cream, and butter (saturated fat) causes an increase in the amount of cholesterol in the blood. It is also believed that carbon monoxide found in cigarette smoke and in mine air where diesel machinery is used helps speed up the formation of cholesterol plaques. An individual's diet and personal habits, therefore, become very im- portant in preventing heart disease. 29 51A FILL IN THE BLANKS WHEN THE ARTERIES CAN NO LONGER SUPPLY OXYGEN TO CERTAIN PARTS OF THE HEART, A OCCURS. . IT IS BELIEVED AND ARE VERY IMPORTANT IN PREVENTING HEART DISEASE. Answer: heart attack; diet, personal habits 52A If enough of the heart muscle has been damaged by a heart attack, the heart will not be able to effectively pump blood to other parts of the body. This happens when the undamaged part of the heart is unable to take over and make up for the damaged part. The condition that occurs in this situation is congestive heart failure, which can cause death. FILL IN THE BLANKS IF THE HEART CANNOT PUMP ENOUGH BLOOD TO THE PARTS OF THE BODY BECAUSE OF DAMAGE TO PART OF THE HEART MUSCLE, OCCURS, WHICH CAN CAUSE DEATH. Answer: congestive heart failure 53A The heart muscle can also be damaged if it has to pump blood through narrowed blood vessels. Blood vessels in the lungs can become narrowed when scar tissue is formed as a result of chronic lung disease. Narrowing of the small blood vessels in the rest of the body can also be the result of such things as exposure to noise. The narrowing of the blood vessels makes it harder for the blood to flow, resulting in high blood pressure and a bigger workload for the heart. If this condition is present over a long period of time, it could cause the heart to wear out more quickly than it would under normal conditions. FILL IN THE BLANKS THE HEART WILL ALSO TEND TO WEAR OUT FASTER IF THE BLOOD VESSELS LEADING TO THE PARTS OF THE BODY ARE ‘ Answer: narrow 30 54A REVIEW LET'S REVIEW THE FUNCTION OF THE LUNGS AND HEART. 10. THE AIR SACS AND THE AIRWAYS MAKE UP THE SYSTEM. MUCUS, HAIRS OR CILIA, AND MUSCLES OF THE BRONCHIOLES ARE ALL OF THE UPPER RESPIRATORY SYSTEM. THE AREA OF THE LUNGS MOST LIKELY TO RECEIVE DAMAGE FROM HARMFUL SUB- STANCES IS THE : WHICH OF THE FOLLOWING IS A SPECIFIC DISEASE OF THE RESPIRATORY SYSTEM? A. BRONCHITIS B. PNEUMONIA C. PNEUMOCONIOSIS D. ALL THE ABOVE THE LARGEST SINGLE FACTOR CONTRIBUTING TO LUNG CANCER IS A. DRINKING B. CIGARETTE SMOKING C. COAL DUST D. FIBROSIS THE CARRY BLOOD TO THE BODY AND THE RETURN BLOOD TO THE HEART. THE SUBSTANCE FOUND IN THE RED BLOOD CELLS THAT CARRIES OXYGEN IS CALLED CARBON MONOXIDE FOUND IN MINES USING DIESEL EQUIPMENT CAUSES A LACK OF IN THE BLOOD. WHITE BLOOD CELLS FIGHT BY MAKING ANTIBODIES AND ALSO CONTAIN THAT HELP THE BLOOD TO CLOT. A CONDITION THAT OCCURS WHEN THE HEART IS UNABLE TO PUMP BLOOD EFFEC- TIVELY TO ALL PARTS OF THE BODY IS A. MUSCLE FATIGUE B. CONGESTIVE HEART FAILURE C. CARDIO-PULMONARY FAILURE D. HEART FAILURE 54A Inswers: 1. respiratory 6. arteries, veins 2. natural defenses 7. hemoglobin 3. alveoli or air sacs 8. oxygen 4. D 9. infection, platelets bh. B 10. B If the correct answers were not clear, review before moving ahead. 55A Liver Function The liver is located just below the rib cage in the upper right corner of the abdomen. It is actually the chemical factory of the body receiving all the blood from the intestines and destroying or changing harmful sub- stances in the blood to harmless ones. The liver works to neutralize harmful chemicals that enter the body as well as chemicals produced by the body when the body no longer needs them. A liver that cannot function, therefore, cannot do this important job. 56A Hepatitis, or inflammation (soreness) of the liver, can be caused by a virus or various chemicals and drugs. The various kinds of hepatitis usually do not create long lasting effects on the body. However, a severe case of hepatitis can result in a scarring of the liver called cirrhosis. Most com- monly, however, liver scarring is the result of drinking excessive amounts of alcohol. If there is enough scarring to hinder the normal function of the Tiver, it will not be able to do the chemical work required by the body, and the level of toxic or harmful substances will build up in the body caus- ing injury, illness, and possible death. FILL IN THE BLANKS CERTAIN CHEMICALS MAY CAUSE AN INFLAMMATION OF THE LIVER KNOWN AS » AND OF THE LIVER MAY RESULT, MAKING THE LIVER UNABLE TO FUNC- TION NORMALLY AND POSSIBLY LEADING TO DEATH. Answer: hepatitis, cirrhosis or scarring 32 57A Kidneys The blood stream carries a variety of substances which are products of the chemical processes of the body. In order for good health to bemaintained, all of these substances must be kept in the proper balance. For these rea- sons, let's now focus attention on the body's filtering system, the kidneys. The kidneys provide a delicate and sophisticated filtering system for the body and are responsible for maintaining this proper chemical balance in the blood. Since the kidneys filter all substances in the blood, these or- gans may be seriously injured by many harmful chemicals which pass through the body. The general appearance of the kidneys is shown in Figure 6A. Artery and Glomeruli J Glomerulus Vein Cortex (outer tissue layer) Ureter FIGURE 6A. THE KIDNEY FILL IN THE BLANK THE ARE RESPONSIBLE FOR FILTERING THE BLOOD AND MAINTAINING PROPER CHEMICAL BALANCE. Answer: kidneys 33 58A The two kidneys are each about 5 inches long and 2 inches wide and are located in the back just below the rib cage. Each one contains over a million microscopic filters, called glomeruli, through which the blood circulates. These filters separate all of the water and salts from the bloodstream and collect the water and salt mixture, called urine, in the kidney. 59A Once the filters do their job, the urine passes from the filters into small, Tong coiled tubes called tubules. The urine, however, still contains sugar that the cells of the tubules must now put back into the blood. These cells remove the sugar and chemicals from the urine by acting Tike a chemical pump, and in this way the kidneys are able to maintain the proper balance needed to keep the body healthy. The tubules then lead into a single tube leading to the bladder where the urine remains prior to elimination from the body. FILL IN THE BLANK TUBULES HAVE THE JOB OF REMOVING CHEMICALS FROM THE Answer: urine 60A The symptoms of kidney disease are often vague and termed nonspecific, meaning that a doctor is often unable to definitely decide on the cause of the illness. For example, high blood pressure may occur if the kidneys cause increased levels of salt and water accumulation in the body, possibly leading to heart strain and heart failure. An increased salt level can also cause edema (swelling) due to the accumulation of fluid in body tissues. A particu- lar type, pulmonary edema, is the accumulation of fluid in the lungs. FILL IN THE BLANK THE SYMPTOMS OF KIDNEY DISEASE CAN BE TRICKY IN THAT THEY ARE Answer: nonspecific 34 61A Some chemicals may directly poison the kidney. It was said before that the function of tubules in the kidneys is to remove harmful chemicals, but by doing this job, the tubules are exposed to high concentrations of these chem- icals and can be poisoned. Kidney poisoning may appear within a few hours after exposure, or possibly not for days following contact with harmful chem- icals. Poisoning of the kidney may cause a person to stop urinating, or allow passage of only a few drops a day. All functions that the kidney nor- mally carries out are thus affected, and congestion results from the accumulation of fluid. Uremia is the name given to the condition that occurs when chemicals produced by the body are allowed to build up. This condition can lead to death. FILL IN THE BLANKS HARMFUL CHEMICALS CAN THE KIDNEYS AND IF A BUILDUP OF FLUID DEVELOPS, A SERIOUS CONDITION CALLED CAN LEAD TO DEATH IF NOT TREATED. i ———————— ————— ———— mm Sm mS eS Answer: poison, uremia 62A Industrial chemicals and industrial accidents can also cause kidney disease. There are several types of kidney disease, each of which may result in the loss of part or all of the kidney's functions. Loss of circulation to the kidneys is one important cause of acute or immediate kidney damage. Kidneys, like the heart, function continuously and require a constant supply of blood and oxygen. Major injuries that result in loss of blood, Tow blood pressure, or poor circulation may cause a lack of circulation and oxygen. Carbon monoxide is an industrial chemical that prevents the circulation of oxygen and may result in kidney damage. 63A Heat exposure can also cause changes in circulation resulting in more blood going to the skin and less blood to the kidneys. This can result in kidney damage if the change is great or if it occurs too fast. Heavy exer- cise causes more blood to go to the muscles, but this change is generally not harmful to healthy young workers. Heavy exercise, however, does increase the risk of kidney damage for older persons. Also, individuals with mild kidney damage may suffer further damage as a result of heavy exercise. 35 63A FILL IN THE BLANKS INDUSTRIAL CHEMICALS AND INDUSTRIAL ACCIDENTS MAY CAUSE IMMEDIATE KIDNEY DAMAGE DUE TO ‘ Answer: loss of circulation 64A Certain chemicals and injuries can break up the red blood cells and re- lease hemoglobin into the bloodstream causing immediate damage to the kidney. Under normal conditions, hemoglobin is prevented from entering into the kid- ney tubes by the membrane surrounding the red blood cells. When these cells rupture, hemoglobin is released into the bloodstream and is able to enter the kidney tubules. The hemoglobin then forms a clump blocking the tubes and stopping the formation of urine and the body's ability to eliminate this waste product. FILL IN THE BLANKS AS A RESULT OF CERTAIN CHEMICALS AND INJURIES, THE RED BLOOD CELLS CAN RE- LEASE INTO THE BLOODSTREAM WHICH THEN ENTERS THE KIDNEYS CAUSING OF THE TUBES. Answer: hemoglobin, blockage 65A Problems that may result in chronic or long-term kidney disease then fall into three categories. The first is injury to large and medium-sized blood vessels, which may decrease circulation to the kidneys. The second category involves damage to the kidney tubes, often the result of an injury or illness. The third problem is high blood pressure, which can cause damage to the small and medium-sized blood vessels of the kidneys. High blood pres- sure is the result of blood vessels that become thickened and narrowed. The kidney then suffers damage from the decreased blood flow. FILL IN THE BLANKS BLOOD VESSELS THAT BECOME NARROWED CAUSE ’ WHICH CAN CAUSE LONG-TERM (CHRONIC) KIDNEY DISEASE. Answer: high blood pressure 36 66A REVIEW LET'S BRIEFLY REVIEW THE INFORMATION CONCERNING THE LIVER AND KIDNEYS. 1. THE LEVEL OF HARMFUL CHEMICAL SUBSTANCES IN THE BLOOD CAN BE REDUCED BY THE CHEMICAL FACTORY OF THE BODY OR THE ‘ 2. WHICH OF THE FOLLOWING IS A DISEASE OF THE LIVER? A. DERMITITIS B. HEPATITIS C. CIRRHOSIS D. BOTH B AND C 3. THE MAIN JOB OF THE KIDNEYS IS TO ACT AS A SYSTEM, KEEPING A PROPER CHEMICAL BALANCE IN THE BLOOD. 4. THE KIDNEYS GET RID OF WASTE IN THE FORM OF AND IN THIS WAY THEY ARE ABLE TO MAINTAIN THE PROPER BALANCE NEEDED TO KEEP THE BODY HEALTHY. 5. KIDNEY DAMAGE CAN BE CAUSED BY A. HIGH BLOOD PRESSURE B. CHEMICALS C. INDUSTRIAL ACCIDENTS D. ALL THE ABOVE Answers: 1. liver 2.0 3. filter 4. urine 5. D If the correct answers were not clear, review before moving ahead. 37 67A Central Nervous System In order for an individual to work or even exist from minute to minute, the body must never cease performing its mechanical functions, such as breath- ing. Besides performing these mechanical functions, an individual must be able to think, experience emotions, and respond to the environment. The nervous system controls all these complicated jobs that the mind and body perform, often while a person remains unaware that these controls are operating. In other words, the nervous system is the control center for the body, letting organs and muscles know when to do something. 68A The nervous system can be broken down into different parts. First, there is the central nervous system which is made up of the brain and the spinal cord; this is the control center of the body. Originating from the brain are 12 pairs of cranial nerves that control vision, the way the eyes work, the senses of smell and hearing, as well as several other functions. These cranial nerves branch out and connect with other nerves extending throughout the body. The spinal cord, an extension of the brain, has 31pairs of nerves that extend and divide throughout the limbs, organs, muscles, and skin. This system is pictured in Figure 7A. ee aan XC Nerve plexus 7 : \ Spinal cord | \X Spinal nerves 0 71) \ ; FIGURE 7A. THE CENTRAL NERVOUS SYSTEM 38 68A FILL IN THE BLANKS THE CENTRAL NERVOUS SYSTEM, THE CONTROL CENTER OF THE BODY, IS MADE UP OF THE AND THE . Answer: brain, spinal cord 69A The nerves that leave and reenter the central nervous system reach every part of the body; this system is called the peripheral nervous system. These nerves are assembled in bundles called plexuses when they leave the spinal cord, but then branch out in a definite pattern to the back, sides, and front of the body. These nerves must also extend through the body to every muscle, since all activity of the body is controlled by nerve signals. For example, the peripheral nerves that branch from the bundle of nerves in the shoulder area affect the skin and muscles of the shoulder and arm allowing them to move. A11 of the muscles that permit body movement, from turning your head back and forth to moving your little finger up and down, are controlled by the periph- eral nervous system. FILL IN THE BLANK THE NERVES THAT SUPPLY THE SKIN, MUSCLES OF THE ARMS AND LEGS, AND THE SHOULDER ARE PART OF THE NERVOUS SYSTEM. Answer: peripheral 70A The brain and spinal cord are capable of sending and receiving messages. For example, if you touch something hot, the peripheral nerves transmit in- formation to the spinal cord and brain, which then transmits information back to the affected area along other peripheral nerves causing certain muscles to expand or contract. As a result, your body is told to pull away from the hot object. Those peripheral nerves that carry messages from the central nervous system are called motor nerves, while those returning messages to the central nervous system are called sensory nerves. 39 70A FILL IN THE BLANKS PERIPHERAL NERVES THAT RETURN MESSAGES TO THE BRAIN ARE CALLED NERVES WHILE THOSE THAT SEND MESSAGES TO MUSCLES AND ORGANS ARE CALLED NERVES. Answer: sensory, motor 71A Nerve messages transferred by means of chemicals and without a person's awareness occur through what is called the autonomic nervous system. There are two divisions of the autonomic nervous system. The first part is concerned with responses to stress and is called the sympathetic nervous system. As the name implies, this part of the system responds in sympathy with an individual's surroundings and feelings. For example, the sympathetic nervous system of a person subjected to a very loud noise (a stressful situa- tion) will quicken the person's heartbeat making the heart work harder. This occurs because the muscles that enlarge or decrease the size of the blood vessels are controlled by sympathetic nerves. Sensory nerves thus activate a response. The second part of the autonomic nervous system is called the parasympa- thetic nervous system. The purpose of this system is to stimulate digestion, empty the bladder, cause mucous secretion, and decrease the heartbeat. FILL IN THE BLANKS THE NERVOUS SYSTEM USES CHEMICALS TO CARRY MESSAGES WITHOUT A PERSON'S AWARENESS OF THE PROCESS. THE NERVOUS SYSTEM AIDS DIGESTION, AND THE SYSTEM RESPONDS TO THINGS SUCH AS AN INDIVIDUAL'S FEELINGS. Answer: autonomic; parasympathetic, sympathetic 72A Injury to the central nervous system is permanent. Once damaged, neither the brain nor the spinal cord can repair itself. However, damage to the peripheral nerves can sometimes be corrected. Chemicals can change or des- troy nerve functions, and paralysis may be the result. But if exposure to certain chemicals is stopped in time, these effects can be reversed. Long- term chemical exposure, on the other hand, may lead to permanent damage. 40 72A FILL IN THE BLANKS DAMAGE TO THE NERVOUS SYSTEM IS PERMANENT WHILE DAMAGE TO THE NERVES CAN SOMETIMES BE CORRECTED. Answer: central, peripheral 73A In spite of all this, the most delicate and most vital part of the body is the brain. Symptoms of dizziness and drowsiness initially indicate that a harmful substance is interfering with the proper function of the central ner- vous system. For example, suppose that a worker's reflexes are dulled. When a worker begins to feel dizzy or drowsy, the brain is acting like an alarm system, trying to tell him that things that should not be there are entering his body and that they are affecting the way the body works. It is important, therefore, to pay attention to warning signals given by your body; it could save your life! FILL IN THE BLANKS THE BRAIN ACTS AS AN SYSTEM AND IS ABLE TO GIVE THE BODY THAT CAN SAVE A LIFE. Answer: alarm, warning signals 74A Musculo-Skeletal System In addition to the systems already mentioned, the body also needs a structural support system. The musculo-skeletal system, made up of bones and muscles, holds the body erect and together. This system performs the same function as the steel framework supporting a building and is made up of sev- eral parts, each with a different function. The bones give the body structure. ® Joints are located between the bones and work somewhat Tike ball bearings, allowing the bones to move freely. e Ligaments hold the bones together. e Tendons firmly hold the muscles to the bones. 41 74A FILL IN THE BLANKS THE SYSTEM PROVIDES FOR THE BODY AND IS MADE UP OF SEVERAL PARTS. Answer: musculo-skeletal, support 75A It is very common to hear people complain of back trouble. This is because the back seems to be the most frequent place for a health problem re- lating to the musculo-skeletal system to occur. Therefore, most of the material in this section will deal with the back. The back is comprised of the bony spinal column and the muscles and ligaments which support and move the spine. The bones of the spine are called vertebrae. The neck is the most flexible section of the spine while the Tower back carries the weight. FILL IN THE BLANKS THE MOST FLEXIBLE PART OF THE SPINE IS THE WHILE THE WEIGHT OF THE BODY IS CARRIED BY THE ‘ Answer: neck, lower back 76A There are 24 blocks of spongy bone (vertebrae) that support the weight of the body. Each of these blocks has winglike projections that surround and protect the spinal cord and nerves. Between the vertebrae are joints that allow flexible movements. There are also cushions called discs located in the joints between the vertebrae. The discs have a jellylike center located in a crisscross network of tough ligaments and act as shock absorbers for the vertebrae (see Figure 8A). Strong, elastic ligaments hold the bones, joints, and discs together by binding the winglike projections to the verte- brae and binding the bones and discs together. These connections keep the spinal column stable. The back muscles surround the bones in the back and are attached to them. Active movements of the body trunk are made possible by these muscles. 42 76A Ligameny Ligament aretr i Body of vertebral bone [a 1 -_ UY) of x > Column for spinal cord Vertebrae 4 FIGURE 8A. MOVEMENT OF THE SPINE FILL IN THE BLANK THE LOCATED BETWEEN THE VERTEBRAE ACT AS SHOCK ABSORBERS. Answer: discs 77A The discs are often blamed for many back problems. Although disc in- juries do cause some back trouble, many disc problems come simply fromgrowing old. Ligaments around the disc begin to dry out and become less elastic beginning at ages 30 to 40. Once dried out, a person can easily snap or break a Tigament by suddenly rotating or bending the spine. If the ligament surrounding the disc has been torn, a ruptured disc can occur and cause pain by pressing on the nerves which enter oo leave the spinal cord. 43 77A FILL IN THE BLANKS BY SUDDENLY ROTATING OR BENDING THE SPINE, AN INDIVIDUAL CAN DAMAGE A CAUSING A BACK PROBLEM. SUCH AN INJURY IS MORE LIKELY TO OCCUR, HOWEVER, BEGINNING AT AGES Answer: ligament; 30-40 78A A victim of a back strain has suffered injuries to the joints and liga- ments. Because only bones show up on X-ray films, it is often difficult to determine exactly what has been injured. Applying too much force to the 1igaments of the spine can cause some of the ligament fibers to tear. This condition causes severe back pain, stiffness, and cramping of the muscles. Although the ligament will heal, a scar will form that is weaker than the original ligament. Repeated back strains will cause the ligaments to become loose, which means that they can be injured more easily. FILL IN THE BLANKS BACK STRAINS ARE THE RESULT OF INJURIES TO THE AND Answer: joints, ligaments 79A An injured joint may have a buildup of new bone around its edges. If an X-ray shows joint injury and bony edges around the joint, this disease is called degenerative arthritis or osteoarthritis. Other joints in the spine must take the load that a damaged joint is no longer capable of handling. This additional load may put stress on the other spinal joints and 1igaments and lead to further strains. 44 80A Other parts of the muscular and skeletal system are constructed similar to the back. That is, they consist of bones, joints, cartilage cushions between joints, ligaments, and tendons. However, they too can be injured in industrial work. Natural body position allows each joint of the body to do the best work. For example, both the hand and the fingers are strongest and most comfortable when extended in a straight line from the arm. The shoulder is strongest and most comfortable when the arms are close to the body. The legs are most comfortable in either of two positions: when the knees are bent at a right angle, or when they are straight. Muscles, ligaments, and joints will become fatigued and may be damaged when performing heavy work or the same work over and over in an unnatural position. 81A Injury to the tendons can be caused by repetitive use of any part of the body in an unnatural position. For example, repetitive use of the hand causes it to become swollen and sore. This condition is called tendonitis. Injuries resulting from unnatural posture can be prevented by using properly designed equipment. Generally speaking, the most comfortable position for performing a task is usually the right position for the anatomy of the body. Workers, in fact, know which position is most comfortable for them when per- forming a specific task. For this reason, designers of industrial equipment should consult workers in order to prevent unnecessary fatigue and injury from unnatural work positions. This can be extremely important in the mining industry, especially when working in low seams and using poorly designed equipment. FILL IN THE BLANK REPETITIVE USE OF A PART OF THE BODY IN AN UNNATURAL POSITION CAUSES INJURY TD THE Answer: tendons 45 REVIEW 82A LET'S REVIEW THE MATERIAL COVERED CONCERNING THE NERVOUS AND MUSCULO-SKELETAL SYSTEM. ON THE RIGHT BY PLACING THE APPROPRIATE LETTER ON THE LINE PROVIDED. 11. 12. THE THE MATCH THE PART OF THE NERVOUS SYSTEM ON THE LEFT WITH ITS FUNCTION PART OF THE AUTONOMIC NERVOUS SYSTEM THAT STIMULATES DIGESTION, EMPTIES THE BLADDER, AND CAUSES MUCUS SECRE- NERVE BUNDLES LEAVING THE SPINAL NERVES THAT OPERATE INDEPENDENTLY OF THE CONSCIOUS MIND TO CARRY OUT LIFE-SUPPORTING FUNCTIONS. THE MAIN CONTROL CENTER COMPOSED OF THE BRAIN AND SPINAL CORD. PERIPHERAL NERVES THAT BRING MES- SAGES BACK TO THE CENTRAL NERVOUS 12 PAIRS OF NERVES THAT COME FROM PERIPHERAL NERVES THAT CARRY MES- SAGES FROM THE CENTRAL NERVOUS 31 PAIRS OF NERVES THAT EXTEND TO THE LUNGS, ORGANS, MUSCLES, AND SKIN. PART OF THE AUTONOMIC NERVOUS SYS- TEM THAT RESPONDS TO STRESS. CENTRAL NERVOUS SYSTEM A. CRANIAL NERVES TION. SPINAL CORD B. PERIPHERAL NERVOUS CORD. SYSTEM C. PLEXUSES MOTOR NERVES BD. SENSORY NERVES AUTONOMIC NERVOUS E. SYSTEM SYSTEM. SYMPATHETIC NERVOUS SYSTEM Fs THE BRAIN. PARASYMPATHETIC NERVOUS SYSTEM G. SYSTEM. H. 1. J. NERVES THAT LEAVE AND REENTER THE CENTRAL NERVOUS SYSTEM IN ALL PARTS OF THE BODY. GIVE THE BODY STRUCTURE. HOLD THE BONES TOGETHER. 46 82A 13. THE FIRMLY HOLD THE MUSCLES TO THE BONES. 14. THE IS THE MOST MOVABLE PART OF THE SPINE AND THE CARRIES THE WEIGHT. 15. TENDONS CAN BE DAMAGED AS A RESULT OF USE OF ANY PART OF THE BODY, AND THIS CAN BE PREVENTED BY USING EQUIPMENT. Answers: 1. D 9. 1 2. F 10. A 3. H 11. bones 4. J 12. Tigaments 5. B 13. tendons 6. G 14. neck, lower back 7. E 15. repetitive, properly designed 83. L If the correct answers were not clear, review before moving ahead. The final part of Section A deals with the parts of the body that enable persons to use, if maintained, their senses of touch, hearing, and sight. 83A Skin The skin, covering about 20 square feet, is the largest organ of the body. It provides initial protection for the body and is the organ that is most 1ikely to be injured in the industrial environment. Of all reported occupational diseases about two-thirds, or 65 percent, affect the skin. The skin is the principal barrier providing the body's main defense attack. As such, the skin is tough, flexible, resistant, relatively water- proof, and beautiful. The skin can thus successfully defend against many attacks, but not all of them. FILL IN THE BLANKS THE IS THE LARGEST ORGAN OF THE BODY, AND IT ACCOUNTS FOR PERCENT OF ALL OCCUPATIONAL DISEASES. Answer: skin, 65 47 84A The dermis and epidermis are the two layers that make up the skin. The outer layer, the epidermis, consists of a densely packed layer of cells, which constantly divide and are replaced by young cells. As a cell gets older it moves toward the outer surface of the skin. During this process, the cells make a tough protein, called keratin, which is resistant to dust, germs, and many chemicals. Keratin and Tayers of dead epidermis cells make up the outermost layer of the skin. This epidermal outer layer produces the skin color that is important in protecting the skin against damage from sun- light. The epidermis also contains sweat glands, hair follicles, and blood vessels, all of which are important in regulating body temperature. In addi- tion, the epidermis contains glands that make a substance that is somewhat like ear wax forming a protective oily film over the outer layers of the epidermis. The epidermis then is protected from chemical and physical injury by three things: the outer layer of dead cells, the tough keratin, and the oily coating. 85A The dermis, or inner layer of skin, is made up of fat and connective tissue. Tt holds the epidermis to the body and provides insulation for the body. The dermis is known as the true skin. When injured, it can form scar tissue and repair itself. It also contains nerves that warn the body of cer- tain changes. A microscopic cross-section of the skin is shown in Figure 9A. Epidermis : A Dermis Keratin Dead cells Hair and hair follicle Oil gland (sebaceous gland) Sweat gland Arteries and veins FIGURE 9A. CROSS-SECTION OF THE SKIN 48 85A FILL IN THE BLANKS THE TWO LAYERS OF SKIN ARE CALLED THE OR OUTER LAYER AND THE OR INNER LAYER. PROTECTIVE DEVICES OF THE OUTER LAYER OF SKIN INCLUDE DEAD CELLS, , AND AN OILY COATING, WHEREAS THE INNER LAYER CONTAINS NERVES FOR WARNING AND IS ABLE TO REPAIR ITSELF BY FORMING Answer: epidermis, dermis; keratin, scar tissue 86A In addition to their useful purposes, both the hair follicles and sweat glands provide a way for substances to enter the body. This characteristic of the skin can cause problems for a person. In fact, according to the National Safety Council, about 700,000 workers have some type of skin disease, and the financial loss from occupational skin disease in the United States exceeds $100 million each year. This loss occurs due to lower productivity, poor morale, turnover, and medical costs resulting from the disease. 87A A big industrial health problem, therefore, does exist in spite of the protective mechanisms of the skin. Most of these problems are the result of irritants. They affect the skin of people in different ways, depending on such things as type of skin, age, sex, season of the year, history of pre- vious skin disease, allergies, and personal hygiene. As a result of these attacks, irritation to the skin develops resulting from exposure to irritants in the work environment. This condition is called industrial dermatitis. Symptoms of dermatitis range from a slight reddening of the skin and mild itching to open sores and swelling. FILL IN THE BLANKS EXPOSURE OF THE SKIN TO CERTAIN IN THE WORK ENVIRONMENT CAN CAUSE INDUSTRIAL . Answer: irritants, dermatitis 49 88A Common causes of dermatitis are: chemical compounds and oils; mechanical agents that cause friction and pressure; physical agents such as heat, cold, light, and radiation; plant poisons; and biological agents including bacteria, fungi, and parasites. These causes can result in dermatitis in various ways. A primary irritant from these categories will cause dermatitis at the site of contact on anyone's skin, but the degree of irritation may vary with the amount of the agent and the length of exposure. Examples of primary irri- tants are heat, friction, acids, or alkalis (compounds able to neutralize an acid). There are, in fact, 2000 chemicals classified as primary irritants, and there are several hundred more added to this list each year. 89A Dermatitis caused by a primary irritant is termed contact dermatitis because it appears at the place the skin has been in direct contact with the irritant but does not spread. It usually disappears when an individual avoids contact with the irritant but will reappear again upon contact. For example, without proper protection, all workers who handle the same amounts of an irritating chemical are likely to develop contact dermatitis on the hands because chemical agents produce the highest percentage of all occupational dermatitis. FILL IN THE BLANKS A IRRITANT CAUSES DERMATITIS ON ANYONE'S SKIN UPON CONTACT, AND AS A RESULT IT IS TERMED Answer: primary, contact dermatitis 90A Several chemical and biological agents are called sensitizers. A sensi- tizer may not cause an initial irritation upon contact; however, after repeated or frequent contact, some individuals may develop an allergic type reaction to a certain material. This is called allergic sensitization derma- titis. An example of an allergic sensitizer is poison ivy because everybody who comes in contact with this plant does not develop an irritation. A reaction to an allergic sensitizer may also occur when the skin comes in contact with substances similar to the original producer of the reaction. These allergic reactions to the sensitizer can recur upon contact even years after the initial reaction. There are also some sensitizers that only affect the skin in the presence of Tight (usually ultraviolet light). These are termed photosensitizers. 50 90A FILL IN THE BLANKS POISON IVY IS AN EXAMPLE OF AN BECAUSE IT MAY NOT CAUSE AN INITIAL IRRITATION UPON CONTACT. Answer: allergic sensitizer 91A Other skin irritants can occur from mechanical causes such as handling fiberglass, where particles from the material stick in the skin causing an itch. However, it is probably the individual's scratching and rubbing that cause the actual dermatitis. Also, irritation can result from physical prob- lems like blockage of hair follicles or sweat and oil ducts. This is often caused by industrial oils. In fact, it is believed that cutting oils are the largest single source of industrial dermatitis. This is generally referred to as oil dermatitis and is commonly known as acne or blackheads. No matter what the cause, the best way to control dermatitis is to pre- vent any contact with irritants. If there is no contact, there can be no dermatitis. This, however, is more easily said than done, especially in an industrial environment. FILL IN THE BLANKS CUTTING OILS CAN CAUSE DERMATITIS, AND THE BEST WAY TO PREVENT THIS OR ANY TYPE OF DERMATITIS IS TO AVOID WITH THE IRRITANT. 92A The Ear In addition to the problems caused by skin irritants, it has been known for more than 100 years that workers employed in noisy jobs develop a greater than average degree of hearing loss. Noise is simply defined as unwanted sound, created by vibrations transmitted in the air that are conducted through solids, Tiquids, or gases and received by the human ear. The louder a noise becomes, the higher is its intensity. Frequency, on the other hand, is the highness or Towness of pitch, and high frequency noises seem to be more 51 92A damaging than low frequency noises. Also, the longer a person is exposed to noise, the greater the hearing damage. FILL IN THE BLANKS UNWANTED SOUND IS CALLED AND FREQUENCY SOUNDS CAUSE MORE HEARING DAMAGE. Answer: noise, high 93A The ear is divided into three parts: the external ear, the middle ear, and the inner ear. Figure 10A shows the various parts of the ear. MIDDLE EAR OSSICLES EAR DRUM HAMMER (Malleus) (Tympanum) ANVIL (Incus) STIRRUP (Stapes) EXTERNAL EAR AUDITORY NERVE OUTER EAR INNER EAR AUDITORY CANAL (Meatus Auditorius) Cochlea Semi-circular Canals Oval Window Round Window EUSTACHIAN TUBE FIGURE 10A. STRUCTURE OF THE EAR The external ear is that part of the ear that is attached to the head and is visible to others. Its main job is to capture and transport sound through the auditory canal to the eardrum (tympanic membrane). The eardrum is very thin, Tike the head on a drum, and when it is hit with sound vibra- tions, it acts like a drum being hit and vibrates back and forth. It is here 52 93A that the first step in the translation of sound waves into nervous impulses takes place and the hearing process begins. FILL IN THE BLANKS SOUND IS CAPTURED BY THE EAR AND IS TRANSPORTED THROUGH THE WHERE IT CAUSES THE TO VIBRATE. Answer: external, auditory canal, eardrum 94A The movement of sound waves passes next to the middle ear which is filled with air and contains a chain of three very small bones (or ossicles). These bones are called the hammer (malleus), anvil (incus), and stirrup (stapes) because they look Tike these objects in shape. The vibration of sound waves causes these bones to move and hit one another. This action, in turn, con- ducts the sound from the eardrum to another membrane called the oval window. One of these three bones, the hammer, rests against the eardrum. At the other end of the middle ear, the stirrup is connected to the inner ear. (Refer again to Figure 10A.) FILL IN THE BLANKS A CHAIN OF THREE BONES, THE » AND TRANSFER SOUND FROM THE MIDDLE EAR TO THE. INNER EAR. Answer: hammer, anvil, stirrup 95A The oval window connects the middle ear to the inner ear. The inner ear has two main parts consisting of a series of cavities and spiraled tubes. Referring again to Figure 10A, the three semicircular canals have the job of maintaining body balance. The other part of the inner ear that is shaped like a snail shell and is lined with very fine hair cells and filled with fluid is called the cochlea. Movement of the oval window causes the fluid in the cochlea to vibrate, stimulating the hairs. A nerve impulse results that in turn stimulates the auditory nerve sending the sound message to the brain. 53 95A FILL IN THE BLANKS THE SNAIL SHELL SHAPED PART OF THE INNER EAR IS CALLED THE AND CONTAINS AND WHICH STIMULATE THE AUDITORY NERVE. Answer: cochlea, fluid, hairs 96A The ear, like other organs of the body, also has several natural de- fenses against injury. Hair and ear wax located in the auditory canal help trap and keep out small objects. The auditory canal is also bent, thus re- ducing the chance of objects entering and damaging the eardrum. Finally, the eardrum and middle ear have the ability to reduce the intensity of noise transmitted to the inner ear. The functioning parts of the inner ear are very delicate and can be damaged easily, resulting in deafness. For this reason, reduction in sound intensity is necessary. CIRCLE THE CORRECT ANSWER AS A MEANS OF NATURAL DEFENSE, THE EAR A. PRODUCES WAX AND HAS HAIR B. HAS A BENT AUDITORY CANAL C. TRANSMITS LOUD NOISE TO THE INNER EAR D. BOTH A AND B E. NONE OF THE ABOVE 97A The ear also can equalize pressure so that the eardrum can vibrate pro- perly. Since the auditory canal and middle ear are filled with air, different air pressures tend to have an effect on the eardrum that separates these two parts of the ear. In order for the ear to adjust to pressure changes, preventing the eardrum from rupture, the middle ear has a safety valve. This safety valve is called the eustachian tube, and it connects the middle ear and the back of the throat. For instance, many individuals feel 54 97A their safety valve open or their ears pop while flying in an airplane or while driving up or down a mountain. If this does not happen automatically, some people try swallowing, yawning, or chewing in order to open the safety valve. FILL IN THE BLANKS ANOTHER DEFENSE MECHANISM OF THE EAR IS ITS ABILITY TO ADJUST TO PRESSURE CHANGE WITH A SAFETY VALVE CALLED THE . Answer: eustachian tube ‘ 98A Noise can startle or annoy a person, interfere with communication, and produce various physical effects such as loss of hearing, pain, nausea, and even Tack of muscle control. Loss of hearing can be either a temporary or permanent injury. Temporary hearing loss occurs from exposure to loud noises for a few hours with normal hearing eventually returning. Permanent hearing loss, however, occurs as a result of disease, physical injury, the aging process (presbycusis), or exposure to loud noise for extended periods of time. FILL IN THE BLANKS HEARING LOSS CAN BE EITHER OR AND WHEN IT OCCURS AS THE RESULT OF OLD AGE, IT IS CALLED : Answer: temporary, permanent, presbycusis 99A There are a number of different factors that have an influence on the effects of noise exposure. These differences include: an individual's sus- ceptibility; the intensity or strength of sound; the frequency of the sound; total time of exposure; length of employment associated with a noisy environ- ment; and other factors, such as whether the exposure to noise was continuous or varied. However, every noise problem has three basic parts: a source, a path along which the sound travels, and a receiver, like the human ear. Noise does, in fact, present a major industrial health problem, especially where workers are exposed to noise over many years of work. 55 99A FILL IN THE BLANK FACTORS SUCH AS THE AMOUNT OF TIME WORKERS SPEND EXPOSED TO NOISE AND WHETHER OR NOT THE NOISE WAS CONSTANT OR VARIED HAVE AN ON THE EFFECTS OF NOISE EXPOSURE ON THE INDIVIDUAL. 100A The Eye Of all the major organs that sustain industrial injuries, the eye is one of the most Tikely to be hurt. The eye itself is housed in cushioning fatty tissue that provides needed insulation for the eye. For additional protec- tion, the eyebrow area above the eye and the cheek ridges below the eye both project beyond the eye itself. The eyelid and front of the eyeball are covered with a mucous membrane called the conjunctiva, and the cornea pro- vides a transparent covering over the outer portion of the eye. The eye has a lens system similar to that of a camera. This system focuses on an image, and special sensory cells in the retina change a visual image into an electrical message that is carried by the optic nerve to the brain. The brain receives the message and interprets it. This process is called seeing. Figure 11A illustrates some of the major components of the eye. 4 Eyelid / ~ p 77 Cornea Conjunctiva X Eyelid \ Retina Lens FIGURE 11A. ILLUSTRATION OF THE EYE 56 100A FILL IN THE BLANKS THE EYE FUNCTIONS LIKE A CAMERA AND A VISUAL IMAGE IS CHANGED INTO AN ELEC- TRICAL MESSAGE BY THE AND THE TRANSMITS THTS MESSAGE TO THE BRAIN SO THAT AN INDIVIDUAL CAN SEE. Answer: retina, optic nerve 101A The cornea and lens are not furnished by a large supply of blood vessels and, as a result, these parts of the eye do not heal rapidly if hurt. Also, the retina or photographic film of the eye is made of mostly nerves, and nerves cannot repair themselves if damaged. In spite of these problems, the eye does have some natural defenses against occupational disease and injury. For example, the bony ridges of the skull around the eyebrow protect the eye from injury due to impact. The cushioning and insulating layers of conjunc- tiva and muscle around the eye also tend to absorb impact. In addition, the fact that the eyeball can be dislodged and come out is actually a defense against injury. The eye also has a unique windshield wiper and washer com- bination similar to that of a car. The blink prevents objects from getting in the eye, and tears have the job of washing objects off the surface of the eye. These defenses, however, are no match for some eye hazards that result from working in an industrial setting. CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING ARE NATURAL DEFENSES OF THE EYE? A. BLINKING B. TEAR RESPONSE C. THE EYEBALLS' ABILITY TO COME OUT D. ALL THE ABOVE Answer: D 57 102A Blows from blunt objects produce pressure on the eyeball and can cause injury; an actual rupture of the eye might occur as the result of an extremely hard blow. Bruises (contusions) on the eye can cause an irreversible injury because blood released during hemorrhaging can actually be harmful to the tissues of the eye. Sharp objects, on the other hand, can cause a tear or cut of the cornea, eyelid, or conjunctiva. 103A Foreign objects, however, produce the most common form of physical in- jury to the eye. Particles traveling at low speed and hitting the eye are likely to lodge in or on the cornea or conjunctiva, whereas those traveling at high speed are likely to lodge within the eye. Generally speaking, foreign bodies that affect the exposed part of the eye are not too serious because they are located away from the apparatus of seeing. The presence of such foreign bodies can result in redness and discomfort, but usually not vision damage. If the person with a foreign body affecting the conjunctiva rubs the eye, the foreign body may be transferred to the cornea where it could become imbedded. For this reason, a medical checkup is advisable, even for something that may at the outset seem minor, like a speck in the eye. Figure 12A tells you what you can do if a foreign object gets in your eye. ER Pull upper eyelid over lower eyelashes Lift eyelid, remove object with sterile gauze CAUTION: DO NOT RUB THE EYE OR USE POINTED INSTRUMENTS! FIGURE 12A. FOREIGN OBJECTS IN THE EYE 58 103A FILL IN THE BLANKS THE MOST COMMON PHYSICAL INJURY TO THE EYE OCCURS AS THE RESULT OF Answer: foreign objects 104A As mentioned, foreign bodies can lodge on or in the eye. Foreign bodies found in the industrial work environment, however, are most likely to affect the cornea or outer part of the eye. When this happens, there can be dif- ferent effects on the eye. Pain can develop because the cornea has many nerves. A foreign particle can stimulate these nerves causing an uncomfort- able sensation. Infection can also occur from bacteria or fungi being trans- ferred to the eye from the fingers. People run this risk when something gets in their eyes, and then they rub the eye. Most importantly, an individual's vision can be obscured if particles lodging on the eye cause scarring. Tissue of the cornea will heal; however, scars can do nothing but harm a person's sight. CIRCLE THE CORRECT ANSWER OBJECTS ON THE EYE CAN CAUSE A. PAIN B. INFECTION C. SCARRING D. ALL THE ABOVE 105A If a foreign object, by chance, penetrates the eye, what is the effect? Infection can occur, but it seems that the speed of an object entering the eye is the determining factor concerning infection. For example, metal ob- jects that enter the eye at high speed create heat upon penetration, and this heat, in fact, sterilizes the wound, helping to prevent infection. Slower moving wood particles do not heat up, and if they get into the eye, dangerous 59 105A infection can occur resulting in vision reduction. In addition to speed, an object's angle at the point of entry determines the amount of damage to parts of the eye such as the cornea, lens, or retina. FILL IN THE BLANK THE DETERMINING FACTOR CONCERNING EYE INFECTION SEEMS TO BE THE OF A FOREIGN OBJECT ENTERING THE EYE. Answer: speed 106A Lens damage is serious because the Tens does not have a good blood supply; consequently, it is slow to heal. Damage to the eye from flying ob- jects causes cell damage as well as hemorrhaging of small blood vessels. In fact, the iron normally found in the blood is actually harmful to the eye. Pure copper particles are even more dangerous. If these particles lodge in the eye, the eye is almost certain to be destroyed as a result of copper poisoning. FILL IN THE BLANKS SERIOUS DAMAGE CAN OCCUR TO THE OF THE EYE BECAUSE IT 15 TO HEAL. Answer: Tens, slow 107A Pain, however, cannot be counted on to warn an individual that a foreign particle has penetrated the eye. In fact, there have been cases where workers barely remember getting something in their eye, think nothing of it due to the lack of pain, and eventually lose sight in the eye as a result of the damage done by the penetrating object. FILL IN THE BLANK AN INDIVIDUAL CANNOT COUNT ON TO BE A WARNING OF EYE INJURY. Answer: pain 60 108A In many industrial work environments, other more serious eye injuries occur as a result of burns. These burns to the eye result from such things as chemicals, specifically acids or alkalis, heat, or radiation. Chemical burns usually produce a scar on the cornea. It is interesting to note that alkalis or lye solutions cause more severe injuries than acids. In fact, with an alkali burn, the eye may not appear to be hurt too seriously on the first day of the injury; however, the condition of the eye will continue to get worse over a period of days. An acid burn, on the other hand, has an initial appearance that gives a good immediate indication of the total eye damage. The difference in reaction to these two chemical substances is due to the fact that acids tend to settle on the protein barrier of the eye pre- venting further penetration into the eye. Alkalis, however, continue to soak through eye tissue as long as they remain there. Heat from such burns can destroy eye and eyelid tissue in the same way it destroys other body tissue. However, eye tissue may not recover as quickly from a burn as skin and muscle tissue. Since involuntary closing of the eye is almost certain response to excessive heat, the 1ids are more likely to be involved in burns than the eye itself. 109A Optical radiation commonly found in industry can also harm the eyes: eo Welding operations create exposure to ultraviolet light. A welder is too close to the arc to be able to look at it without a proper eye- shield and therefore rarely suffers such injury. Exposure in this case is more likely to injure the cornea of a welder's helper or other bystander. The harmful effects of ultraviolet (UV) radiation on the cornea add up, and the painful result may be delayed. eo UV radiation penetrates the cornea of the eye only at high concentra- tions because the surface of the cornea acts to filtzr it out. Damage to the retina, therefore, would be unlikely if the on'y source of UV radiation was a welding flash. eo Unlike ultraviolet, infrared radiation passes easily through the cornea. The energy of the radiation is then absorbed by the retina. Eye damage due to infrared radiation is less common today than in the past. However, cataracts (clouding of the lens) still result as an occupational disability among some glass blowers. 61 109A FILL IN THE BLANKS SERIOUS INJURIES TO THE EYE FROM BURNS RESULT FROM AND AS WELL AS AND RADIATION. Answer: chemicals, heat, ultraviolet, infrared 110A In concluding the first section of this programmed instruction course, let's review and determine what has been learned about the eyes, ears, and the skin. 1. SKIN IRRITATION CAUSED BY DIRECT CONTACT WITH CHEMICALS A. ALWAYS APPEARS AT THE POINT OF CONTACT B. GOES AWAY WHEN CONTACT IS ENDED C. DOES NOT SPREAD TO OTHER PARTS OF THE BODY D. ALL THE ABOVE E. NONE OF THE ABOVE 2. TYPE OF SKIN, AGE, SEX, ALLERGIES, AND PERSONAL HYGIENE OR CLEANLINESS DETERMINE A. A HISTORY OF SKIN DISEASE B. HOW OFTEN A SKIN DISEASE WILL OCCUR C. THE EFFECT OF A SKIN IRRITANT D. NONE OF THE ABOVE 3. THE MOST COMMON CAUSES OF DERMATITIS RESULT FROM » PLANT POISONS, AND . » AND AGENTS. 4. THE HIGHEST PERCENT OF ALL OCCUPATIONAL DERMATITIS IS CAUSED BY 62 110A THE LARGEST SOURCE OF INDUSTRIAL DERMATITIS OCCURS AMONG INDIVIDUALS WORKING WITH A. PLANTS B. CUTTING OIL C. HEAT D. BIOLOGICAL AGENTS THE HEARING PROCESS BEGINS WHEN SOUND A. IS CAPTURED B. STARTLES AN INDIVIDUAL C. VIBRATES THE EARDRUM BACK AND FORTH D. NONE OF THE ABOVE THE TRANSFER OF SOUND TO THE INNER EAR OCCURS AS A RESULT OF A. THE ACTION OF THE MIDDLE EAR B. VIBRATION OF THE HAMMER, ANVIL, AND STIRRUP C. A CHAIN OF THREE SMALL BONES HITTING ONE ANOTHER D. BOTH B AND C E. ALL THE ABOVE BALANCE IS MAINTAINED BY THE ] AND THE STARTS A NERVE IMPULSE WHICH IS SENT TO THE BRAIN AS A SOUND MESSAGE. WHICH ONE OF THE EAR'S NATURAL DEFENSES HAS THE JOB OF EQUALIZING PRES- SURE CAUSING THE EAR TO POP? A. HAIR AND WAX BUILDUP B. A STRAIGHT AUDITORY CANAL EUSTACHIAN TUBE cD D. NONE OF THE ABOVE 63 110A 10. NOISE PROBLEMS HAVE SEVERAL BASIC PARTS CONSISTING OF A. A SOURCE AND RECEIVER B. INDIVIDUAL SUSCEPTIBILITY C. PATH FOR THE SOUND D. BOTH A AND C E. ALL OF THE ABOVE 11. A MUCOUS MEMBRANE COVERING THE EYE IS CALLED THE AND THE TRANSPARENT COVERING OVER THE OUTER PORTION OF THE EYE IS THE ‘ 12. WHICH OF THE FOLLOWING ARE NOT NATURAL DEFENSES OF THE EYE A. B. C. D. E. A LARGE SUPPLY OF BLOOD BONY RIDGES OF THE EYEBROW THE ABILITY OF THE EYEBALL TO BE DISLODGED BLINK AND TEAR SYSTEM ALL OF THE ABOVE 13. FOREIGN BODIES RESULTING FROM WORK ACTIVITIES IN THE INDUSTRIAL ENVIRON- MENT MOST LIKELY WILL AFFECT THE OF THE EYE CAUSING POS- SIBLE PAIN, INFECTION, OR SCARRING. 14. MINERS IN WHAT INDUSTRY RUN THE HIGHEST RISK OF EYE DESTRUCTION IF THE PRODUCT OF THAT INDUSTRY WOULD HAPPEN TO LODGE IN THE EYE? COAL TIMBER COPPER URANIUM 15. MINERS USING WELDING EQUIPMENT SHOULD AVOID EXPOSURE TO A. EXPOSED LIGHT INFRARED LIGHT SPECTRAMATIC LIGHT ULTRAVIOLET LIGHT Answers : — 10. 11. 12. 14. 15. 110A D C chemicals, physical, mechanical, biological chemicals B ¢ E semicircular canals, cochlea c E conjunctiva, cornea A cornea C D If the correct answers were not clear, review before moving ahead to Section B. Hygiene and the Human Body." Next, let's examine the Recognition of Health Hazards. This concludes the first section of the course, "Industrial 65 = Leh . oe y- ay o “a INDUSTRIAL HYGIENE FOR THE MINING INDUSTRY SECTION B "RECOGNITION OF HEALTH HAZARDS" nc unlighs x 1B This frame begins Section B of the Industrial Hygiene course. It is en- titled "Recognition of Health Hazards." This section will concentrate on toxicology, routes of entry, dosec- response relationships, threshold limit values, and the recognition of various environmental stress factors found in the workplace that directly affect the human body. Specifically, the objective will be to recognize the effects of toxic substances such as liquids, vapors, gases, mists, fumes, and dust, as well as environmental factors such as radiation, noise, vibration, and tem- perature and pressure extremes. In addition, time will also be spent on recognizing both mental and physical ergonomic stresses. Again, as in Section A, questions will be asked throughout this section. Remember to answer the questions before checking the correct answer immedi- ately following the question. TRUE OR FALSE SECTION B IS TO BE COMPLETED IN A DIFFERENT WAY THAN SECTION A. Answer: false 2B Toxicology Each year there are hundreds of new chemicals produced. Many are poten- tial hazards. It is for this reason that a knowledge of toxicology is important in an industrial environment. Toxicology is nothing more than the study of the nature and action of poisons. Industrial toxicology is concerned with the effects poisons have on individuals who have been exposed while at work. FILL IN THE BLANKS THE STUDY OF THE EFFECTS POISONS HAVE ON INDIVIDUALS IN THE WORKPLACE IS TERMED ‘ Answer: industrial toxicology 69 3B There are, however, degrees of safeness and harmfulness for all mate- rials. Any substance can be harmful to an individual if that individual is exposed to just the right amount. Some substances may produce a harmful effect in all individuals. There are even those substances that may only affect certain people and not others (individual differences) due to the rate of an individual's metabolism. Also, other substances may affect only cer- tain parts of the body. This harmful effect on humans is referred to as toxicity. It should be pointed out that the terms toxicity and health hazard are not the same. Toxicity is merely the ability of a material to produce injury or harm whereas a health hazard occurs if it is possible that a cer- tain material in a specific amount will cause an injury under certain condi- tions. Toxicity is dependent upon the dose, rate, method, and the location where a toxic substance enters the body. Toxicity is also influenced by an individual's state of health, individual differences, the ability of an in- dividual to resist stress (tolerance), diet, temperature, and age. FILL IN THE BLANKS THE ABILITY OF A MATERIAL TO PRODUCE INJURY OR HARM TO AN INDIVIDUAL IS TERMED . TOXICITY 1S UPON AND IS BY A VARIETY OF FACTORS. Answer: toxicity; dependent, influenced 4B There are, however, three differences when considering toxicology and its effects at home and at the workplace. First, when considering how a substance is taken into the body, the most common way at home is by way of mouth whereas at work it is through inhalation or the respiratory tract. The second difference is that poisoning at work tends to occur over longer periods of time whereas at home, poisoning occurs right away. The final difference is that poisoning at work is generally a result of exposure to a variety or mixture of substances compared with usually a single substance being at fault in the home environment. Harmful industrial poisoning usually occurs without voluntary action on the part of the individuals poisoned and perhaps without them even being aware that it is happening. At home, on the other hand, persons are usually poisoned accidentally by ingesting a poisonous substance. 70 FILL IN THE BLANKS 4B AT WORK AT HOME TYPE OF ENTRY - MOUTH TYPE OF POISONING - CHRONIC TYPE OF SUBSTANCE - ONE SUBSTANCE Answers: AT WORK AT HOME Type of Entry - Inhalation Mouth Type of Poisoning - Chronic Acute Type of Substance - Mixture One Substance (Once complete, this chart can serve as a ready reference comparing poi- sonings at work and at home.) 5B Routes of Entry In order to do any damage to the human body, these toxic substances have to enter or come in contact with the body. This is accomplished in various ways, usually by one of three routes. These are termed routes of entry, and they occur by way of inhalation, ingestion, or skin contact. Figure 1B shows the various routes of entry. Inhalation Skin Contact (penetration or absorption) FIGURE 1B. ROUTES OF ENTRY 71 5B FILL IN THE BLANKS THERE ARE MAIN ROUTES OF ENTRY INTO THE BODY: ’ » AND ‘ Answer: three, ingestion, absorption, inhalation 6B Ingestion or swallowing of toxic substances can occur as a result of eating or smoking with contaminated hands in a contaminated work area. As a result, the toxic substance is swallowed and absorbed in the digestive system and picked up by the blood. This situation is most likely to occur with larger size particles usually over 2 microns in size. However, if there is enough of the contaminant existing so that it can be ingested, the chance of inhaling the toxic material will probably also exist. FILL IN THE BLANK EATING WITH DIRTY HANDS CAN RESULT IN OF HARMFUL SUBSTANCES. Answer: ingestion 7B Skin absorption occurs when the body comes in contact with a toxic agent. This type of exposure ranks first in the cause of occupational disease, but is not necessarily the most severe. Such an exposure can cause a reaction on the surface of the skin, or the toxic substance may penetrate the skin in a sufficient amount to cause either sensitization to repeated exposures or poi- soning to other systems of the body. CIRCLE THE CORRECT ANSWER THE ROUTE OR MODE OF ENTRY THAT RANKS FIRST IN OCCURRENCE IN THE INDUSTRIAL WORK ENVIRONMENT IS: A. OCCULAR B. INGESTION C. INHALATION D. SKIN ABSORPTION 72 eB Inhalation is the route of entry that is of prime importance and concern in the industrial environment due to the speed of toxic substance can enter the lungs, pass into the blood, and reach different parts of the body causing its harmful effects. This situation occurs when small particles, usually less than 5 microns in size, are breathed in. Once inside the body, the toxic substance usually affects the functioning tissues of the Tung. An important difference, however, between inhalation and the other two modes of entry is that in the case of inhalation the toxic substance enters the arterial blood directly, whereas with ingestion and absorption it doesnot. CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING ROUTES OF ENTRY IS OF MOST IMPORTANCE IN THE WORKPLACE? A. OCCULAR B. INGESTION C. INHALATION D. ABSORPTION 9B Remember, a toxic substance can cause either acute or chronic poisoning. Acute poisoning is usually severe, happens suddenly, and is the result of a single dose of a substance that is absorbed rapidly. For example, carbon monoxide produces acute poisoning. Chronic poisoning, on the other hand, occurs over a long period of time in relatively small dosages. An example of a chronic poisoning condition would be coal workers' pneumoconiosis. FILL IN THE BLANKS TOXIC POISONING CAN EITHER BE OR Answer: chronic, acute 10B The severity of a toxic substance, however, depends on the amount of that substance in the body. This in turn depends on the substance's ability to be dissolved before absorption, or the body's ability to make the sub- stance non-harmful (detoxification), and the rate of elimination (excretion) of the substance from the body. 73 10B FILL IN THE BLANK THE SEVERITY OF A TOXIC SUBST/NCE DEPENDS ON THE OF THE SUBSTANCE IN THE BODY. SS en en Ee a Answer: amount 11B Dose-Response Relationship Since the severity of a toxic substance depends on the amount or dose of that substance, a single large dose can produce a response greater than the same dose administered over a longer period of time. The body does respond in some way to any amount of a substance which enters or touches it. However, the type of response will differ depending on the type and amount of the substance. For this reason, anything can be harmful in a large amount, but in small amounts, the same substance can be relatively harmless. Such a statement can be explained and illustrated by what is called a dose-response relationship. (See Figure 2B.) Death Disease Impairment Health Limit of Normal Adjustment Increasing Response of the Body ol——— ——— — ———_— | | | | | c 0 A B Increasing Doses iS DOSE FIGURE 2B. DOSE-RESPONSE RELATIONSHIP 74 11B FILL IN THE BLANKS THE FACT THAT THE BODY WILL RESPOND DIFFERENTLY DEPENDING ON THE AMOUNT AND TYPE OF A SUBSTANCE CAN BE SHOWN BY A - RELATIONSHIP. Answer: dose-response 12B The body is continuously working to keep things constant even though it is exposed to various doses of different substances. It does this by chang- ing the heart rate, the respiration rate, and eliminating chemicals from the body. People differ in their ability to perform these functions. This is partly due to age, an individual's health and diet, and partially because of inherited characteristics. 13B Because these differences exist, there are great variations in the effect of the same dose of chemicals on different people. This is the result of individual differences. It is never absolutely certain that a particular level of exposure will not injure a person because of the occurrence of in- dividual differences. Also, certain substances have little if any harmful effects on the body if the body is only exposed to that particular substance. However, certain substances in combination with other substances can become harmful. This is called a synergistic effect. FILL IN THE BLANKS THE FACT THAT CERTAIN SUBSTANCES AFFECT PEOPLE IN DIFFERENT WAYS IS THE RESULT OF WHEREAS THE COMBINATION OF CERTAIN SUBSTANCES PRODUCING A TOXIC EFFECT IS THE RESULT OF A EFFECT. Answer: individual differences, synergistic 75 14B Threshold Limit Values In order that exposure to substances is kept at a safe and reasonable level, permissible exposure values, or more correctly, Threshold Limit Values (TLV's) have been established. Threshold Limit Values, according to the Amer- ican Conference of Governmental Industrial Hygienists, "refer to airborne con- centrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed without adverse effect." More specifically, TLV's represent the amount of a substance to which normal, healthy adults can be exposed during an 8-hour day throughout their working lives without the possibility of harm. FILL IN THE BLANK THE ESTABLISHED GUIDE USED WHEN SAMPLING FOR CHRONIC EXPOSURES OF HARMFUL SUBSTANCES IS THE FOR A PARTICULAR SUBSTANCE. Answer: TLV 158 Each year there is a Tist adopted that indicates TLV's for over 400 toxic substances. These TLV's will give permissible concentrations in cer- tain units of measurement. For example, vapors or gases are expressed as parts per million (ppm) in the air. Particles of solid or liquid matter such as dust, fumes, and mists are expressed as milligrams per cubic meter of air (mg/m3). FILL IN THE BLANKS TLV'S ARE EXPRESSED IN AND Answer: ppm, mg/m3 16B Ideally, the reason for TLV's is to prevent an individual from experi- encing harmful irritation, narcosis (stupor or unconsciousness), nuisance, or any impairment of health resulting from overexposure to potentially harmful substances. A certain number of workers may experience only discomfort from a cer- tain concentration of a substance at or below the threshold Timit whereas others, probably a smaller number, may develop an actual occupational illness. 76 17B Again, TLV's should usually be used as guides. However, there are cer- tain substances that have what is called a ceiling value. This value is one that should not be permitted to be exceeded for any reason or for any length of time. Such substances are designated with the letter "C" before the name of the substance when looking at information concerning TLV's. Also, when looking at TLV information, substances that can enter the body by absorption through the skin are identified by the designation "SKIN," following the name of the substance. FILL IN THE BLANKS EXPOSURE LIMITS THAT SHOULD NOT BE EXCEEDED FOR ANY REASON OR FOR ANY LENGTH OF TIME ARE CALLED . En mn eS SS Sm Answer: ceiling values 188 Time weighted averages, or an average taken by sampling concentrations at certain times during an individual's period of exposure at work, permit what are called excursions above the TLV for certain substances. This simply means that an individual is allowed to be exposed to more of a certain sub- stance than the TLV allows. However, for the amount of time during the day the exposure exceeds the TLV, an equal amount of work time must also be spent at an exposure level less than the TLV during the day. There is, however, a Timit to the excursion that is allowed above an established TLV, and in some cases excursions can be calculated over a workweek rather than a workday. The excursion, or amount the TLV's can be exceeded at times without in- jury to health, depends on the nature of the substance, whether or not at high concentrations it will produce acute poisoning, how many times these high concentrations occur, and the length of time of the exposure. FILL IN THE BLANK AT TIMES TLV'S CAN BE EXCEEDED CAUSING ABOVE THE TLV FOR A PARTICULAR SUBSTANCE. Answer: excursions 77 198 Some substances, when they exceed a recommended TLV, cause physical irritation but not physical injury or harm. Even if this is the case, such substances should be watched closely because it is believed that the physical irritation caused may in fact aid in the development of actual physical harm. These substances are classified as nuisance particles. They are particles of solid or Tiquid matter that occur in the workplace and can be inhaled but produce no harmful effect over long periods of time. 20B Because these particles can accumulate, there should be some control placed on the amount breathed by an indiyidual. When, for example, the amount of Si02 (silica) in a dust sample is less than 1 percent, the recom- mended TLV for that substance is 10 mg/m3. The particular TLV for less than 1 percent silica also applies to other substances found in the air that have no specific threshold 1imit such as portland cement and limestone. CIRCLE THE CORRECT ANSWER INDIVIDUALS WORKING WITH LIMESTONE WOULD MOST LIKELY COME IN CONTACT WITH: A. NUISANCE PARTICLES B. IRRITANTS C. ASPHYXIANTS D. NONE OF THE ABOVE Answer: A 21B There are also several gases and vapors that act as simple asphyxiants causing unconsciousness or death if present in high concentrations due to lack of oxygen. An example of such a substance is nitrogen. However, a TLV for nitrogen may not be recommended because in this case the factor deter- mining asphyxiation is the availability of oxygen. Carbon monoxide, on the other hand, is an example of a chemical asphyxiant with a TLV of 50 ppm. In this case, oxygen is not a limiting factor because carbon monoxide actually prevents the body from utilizing oxygen. 78 22B Added stress from such physical factors as heat, ultraviolet and ionizing radiation, humidity, pressure,and vibration actually can change or alter threshold limits. In fact, most of these physical stresses actually act to increase the harmful response of a substance. FILL IN THE BLANKS THRESHOLD LIMITS CAN ACTUALLY BE CHANGED BY HOWEVER, TLV'S ARE NOT EVEN RECOMMENDED FOR BECAUSE AVAILABILITY OF OXYGEN IS THE MAIN FACTOR. Answer: physical stress, simple asphyxiants 23B LET'S PAUSE AND REVIEW THE INFORMATION THAT HAS BEEN COVERED TO THIS POINT. 1. THE ABILITY OF A SUBSTANCE TO CAUSE INJURY IS TERMED WHEREAS A OCCURS IF IT IS POSSIBLE THAT A SUBSTANCE WILL CAUSE INJURY. 2. INDUSTRIAL POISONING USUALLY OCCURS WITHOUT ACTION BY AN INDIVIDUAL. 3. THE THREE MAIN ROUTES OF ENTRY ARE AND ‘ 4. MATCH THE POTENTIAL HEALTH HAZARD ON THE LEFT WITH ITS PRIMARY ROUTE OF ENTRY TO THE BODY ON THE RIGHT BY PLACING THE LETTER OF THE ROUTE OF ENTRY ON THE LINE PROVIDED IN FRONT OF THE HEALTH HAZARD. (ROUTES OF ENTRY MAY BE USED MORE THAN ONCE.) 1) EATING LUNCH IN A WORK AREA A. INHALATION 2) AIRBORNE CONTAMINANTS IN WORK AREAS B. SKIN ABSORPTION 3) SOLVENTS USED TO CLEAN HANDS C. INGESTION S ) EATING CANDY BARS IN WORK AREAS ia § ne & ARE rn | 5) SOLVENTS USED TO CLEAN WORK CLOTHING 79 23B 5. THE SEVERITY OF A TOXIC SUBSTANCE DEPENDS ON THE OF THE SUB- STANCE IN THE BODY. 6. INCREASING THE DOSE OF A TOXIC SUBSTANCE WOULD TEND TO CAUSE AN ADVERSE REACTION TO ‘ 7. INDIVIDUAL DIFFERENCES CAUSE PEOPLE TO REACT TO SUBSTANCES THAT ENTER THE BODY. 8. THE AMOUNT OF A CERTAIN SUBSTANCE TO WHICH A PERSON CAN BE EXPOSED DURING AN 8-HOUR WORKDAY IS INDICATED BY THE FOR THAT SUBSTANCE . 9. TRUE/FALSE - CEILING VALUES CAN, ON OCCASION, BE EXCEEDED FOR SHORT PERIODS OF TIME. 10. TRUE/FALSE - NUISANCE PARTICLES DO NOT HAVE ESTABLISHED TLV'S DUE TO THE FACT THEY CAUSE NO PHYSICAL HARM. Answers: 1. toxicity, hazard 6. increase 2. voluntary 7. differently 3. inhalation, skin absorption, 8. TLY ingestion 9. false 4. C, A,B. C,B 10. false 5. amount If the correct answers to these questions were not clear, review before moving ahead to the next frame. Before moving ahead, remember that in Section A there were four basic classifications of stress: chemical, physical, biological, and ergonomic. Three of these classes of stress (chemical, physical, and ergonomic) are more common in the mining industry than biological stress. For this reason, the final parts of Section B will deal mostly with the recognition of certain health hazards in these three areas. 80 24B Chemical Hazards Chemical hazards occur when there are excessive airborne amounts of mists, vapors, gases, or solids in the form of dusts or fumes. These chemi- cal substances can cause inhalation or respiratory problems resulting from a lack of oxygen or harmful contaminants in the air. They can also be swal- Towed causing irritation and damage to the body. In addition, they may also act as skin irritants or become harmful as a result of absorption through the skin. This is the case with some solvents. CIRCLE THE CORRECT ANSWER CHEMICAL SUBSTANCES CAN CAUSE A. RESPIRATORY PROBLEMS B. IRRITATION OR HARM FROM INGESTION C. [IRRITATION OR HARM FROM SKIN ABSORPTION D. ALL THE ABOVE Answer: D 25B Solvents Due to the widespread industrial use of solvents, the possibility of a health hazard exists. Therefore, to get a particular job done safely using solvents depends on the proper selection, use, handling, control, and under- standing by the employee of what solvents are made of. The word solvent means a substance which can dissolve another substance. Most solvents are organic compounds (compounds containing carbon). Some examples are benzene, carbon tetrachloride, and gasoline. The most common solvent, however, is water. Because there are so many solvents being used, it is a good practice to always label a solvent for recognition so that the user will know the name and composition of the substance. FILL IN THE BLANKS AN ORGANIC COMPOUND THAT CAN DISSOLVE ANOTHER SUBSTANCE IS CALLED A AND DUE TO THE FACT THERE ARE SO MANY, THEY SHOULD BE TO INSURE SAFE USE. Answer: solvent, labeled 81 26B Labeling of solvents indicating what they are made of, their effect on an individual's health, and whether or not they present a fire hazard is very important. In fact, an individual really should not use any solvent that is not properly labeled due to the health hazard that could result. For example, if a labeled harmful solvent had been repeatedly used on the job and then a less harmful unlabeled one substituted in its place, but at some later date an unlabeled harmful solvent was used again without the workers' knowledge, a health problem would exist. Information concerning solvents being used by the workers in a particular job setting is therefore desirable for a healthy work environment. Trichlorethyl a a Warning! Volatile Solvent ». Avoid prolonged or 1epeated breath- * Use with adequate ventilation. . ing of vapor. * This material or its vapor in contact Do not take internally. with flames or hot glowing surfaces » Avoid prolonged or repeated contact with may form corrosive acid fumes. skin. * Keep out of reach of children. First Aid: Internal: If swallowed, if conscious, make patient vomit immediately by putting finger down throat or by giving warm mustard water or salt water freely, Call a physician immediately.’ Do not give anything by mouth to an unconscious person. If affected by vapors, move to fresh air _If breathing has stopped, apply artificial respiration. External: In case of contact, immediately flush skin or eyes with plenty of water for at li:ast 15 minutes; for eyes, get medical attention. Remove and wash clothing before reuse. Size Cat. No. For laboratory or manufacturing use. Not for drug use. IT-1180 — ——— Label No. 318-73 Preiser SCIENTIFIC, CHEMICAL, MINING AND INDUSTRIAL PRODUCTS Jones and Oliver Streets > St. Albans, West Virginia 25177 FIGURE 3B. SOLVENT LABEL FILL IN THE BLANKS IF SOLVENTS ARE BEING USED ON THE JOB, CARE SHOULD BE TAKEN TO THE SOLVENTS BEING USED IN ORDER TO HELP PREVENT POSSIBLE HAZARDS. Answer: label, health 82 278 The physical effects an individual receives from solvent exposure come mainly from skin contact and inhalation of solvent vapors, the gaseous form of liquid. Ingestion is normally not a route of entry for solvents. The immediate physical effects produced from a high level of exposure to harmful solvent vapors are irritation to the respiratory tract as well as possible asphyxiation. Increased exposure over long periods of time, however, can cause paralysis of the central nervous system. Low level exposure to sol- vents, on the other hand, causes lack of coordination, drowsiness, and other similar symptoms that resemble drunkenness and can lead to an increase in accident proneness on the job. Also, damage to the blood, lungs, liver, kidneys or other critical organs of the body can result from low-level expo- sure to some solvents. CIRCLE THE CORRECT ANSWER WHICH METHOD OF EXPOSURE TO ORGANIC SOLVENTS IS LIKELY TO HAVE THE LEAST PHYSICAL EFFECT ON THE BODY? A. INHALATION B. SKIN CONTACT C. INGESTION D. NONE OF THE ABOVE Answer: C 28B Due to the possible health hazards that do exist if solvent vapors are present in the work area, detection becomes an important factor. However, when trying to judge whether solvent vapors have reached a dangerous level, neither odor or irritation is an accurate detecting device. Individuals who work around solvents should take the time to learn the exact characteristics of all the solvents they use and the safety precautions that are necessary. FILL IN THE BLANKS IN THE DETECTION OF HARMFUL SOLVENT VAPORS, NEITHER NOR PROVES TO BE ACCURATE Answer: odor, irritation 83 29B If a health hazard does exist from the use of solvents, the seriousness of the situation is always a concern. The severity of a hazard that results from using solvents is determined by the following factors: e How the solvent is used. e Toxicity of the solvent. e Type of job which determines how the workers are exposed. e Work pattern. eo Duration of exposure. eo Operating temperature. eo Exposed liquid surface. e Ventilation controls used. e Evaporation rate of the particular solvent. eo Pattern of air flow. e Concentration of vapor in the work area. ® Housekeeping practices. The seriousness of a solvent hazard, therefore, is determined partly by the toxicity of the solvent. The conditions of a solvent's use such as who used it, what was used, how and where the solvent was used, and how long it was used, are also important in such a determination. FILL IN THE BLANKS THE SEVERITY OF A SOLVENT HAZARD IS DETERMINED BY THE OF THE SOLVENT AND THE OF THE SOLVENT'S USE. Answer: toxicity, conditions 308 Employees working on the job can come in contact with solvents in three different ways. The first is direct contact which usually is the result of hand operations. Examples of this type of contact would be repair of equip- ment, cleanup of solvent spills, or manual cleaning using cloths or brushes 84 30B with solvents on them. The second category is intermittent or infrequent con- tact that occurs under conditions in which the solvent is semi-contained and exposure can be controlled. Examples of this type contact are spray painting in a spray booth equipped with ventilation, vapor degreasing in a tank with ventilation, or transferring solvents to other than their original containers. The final category is termed minimal contact and is characterized by remote operation of equipment that is isolated from the individual's work area. Contact in this situation is minimal due to the fact the solvent is contained in a closed system and is not released into the working atmosphere. This would tend to occur, for example, in the chemical factories where solvents are produced. FILL IN THE BLANKS CONTACT WITH SOLVENTS IN JOB OPERATIONS THAT INVOLVE THE USE OF THESE CHEMI- CALS ARE CATEGORIZED BY THE METHOD OF CONTACT AS EITHER ’ Answer: direct, infrequent, minimal 31B Industrial Skin Disease Remember in Section A that there were two types of dermatitis mentioned: those resulting from a primary irritant and those resulting from sensitiza- tion. The main cause of occupational dermatitis in the industrial environ- ment is from chemical agents. Some substances such as solvents and epoxy resin can produce both primary and sensitization dermatitis. Because indus- trial skin disease accounts for one-half to two-thirds of all occupational Jlnsss reported, attention should be given to the recognition of this problem. FILL IN THE BLANKS SOLVENTS AND EPOXY RESINS ARE EXAMPLES OF CHEMICALS THAT CAN CAUSE BOTH AND DERMATITIS. Answer: primary, sensitization 85 32B . Industrial dermatitis is simply an irritation of the skin resulting from exposure to certain substances (chemical compounds, mechanical, physical and biological agents, and plant poisons) in the work environment. Symptoms of this condition range from a slight reddening of the skin along with mild itching to open sores that may or may not be swollen. In most cases, however, an individual is not able to positively identify the irritant causing the problem from the characteristic appearance of the skin. FIGURE 4B. INDUSTRIAL DERMATITIS ON HANDS 33B If a case of dermatitis is identified at the workplace, a search should begin for the location of possible exposure so that the skin irritants or sensitizers that are being used can be identified. If the cause cannot be found at work, chances are that the dermatitis is due to activities at home. In either case, the individual should receive medical treatment as scon as possible. FILL IN THE BLANKS ONCE DERMATITIS IS RECOGNIZED, A SHOULD BEGIN FOR WHATEVER CAUSED THE PROBLEM AND PROVIDED FOR THE INDIVIDUAL AS SOON AS POSSIBLE. Answer: search, medical treatment 86 34B In addition to the irritants that cause dermatitis, there are many indi- rect factors that interact to produce a skin problem. These indirect causes consist of such things as habits of personal hygiene or pre-existing skin diseases that a person might already have. Examples of indirect causes might be hereditary conditions affecting the skin, acne, eczema, or psoriasis. Ner- vous disorders can also trigger a reaction that could produce a local or general rash on certain areas of the body. FILL IN THE BLANKS IRRITANTS AS WELL AS MANY INTERACT TO PRODUCE DERMATITIS. Answer: indirect factors 358 Chemicals, in addition to causing dermatitis, can also cause burns to the skin destroying body tissue. The severity of such a burn depends on the harshness of the chemical, what the chemical consists of, the temperature of the chemical, and the length or duration of the chemical's contact with the body. The burns that result can be either first, second, or third degree. Third degree burns, however, are the most severe. First degree burns produce redness and heat at the sight of injury along with itching, burning, and pain. Second degree burns are more painful and damage deeper portions of the skin with blisters being formed. Third degree burns are the most severe and involve the actual loss of skin and other body tissue with the area of injury being white instead of red. Third degree burns, however, are not very painful at first because nerves in the area of injury have usually been destroyed or their function impaired. The danger that results to an individual's life from any burn is infection, Toss of body fluid, and shock. BURN CLASSIFICATIONS Class Symptoms First Degree eReddened outer skin EIT * Swelling Second Degree *Reddened Skin IGE *Blisters (open or closed) *Damaged underskin LL RO ETT * Skin is destroyed Burns *Underskin tissue exposed and damaged * Area may be charred FIGURE 5B. BURN CLASSIFICATIONS 87 358 FILL IN THE BLANKS IN ADDITION TO CAUSING DERMATITIS, CHEMICALS CAN ALSO CAUSE THAT CAN BE CLASSIFIED AS EITHER ’ » OR DEGREE. Answer: burns, first, second, third 36B Chemical burns can also occur to the eye. The eye, however, has a moist surface and tears that help dilute and remove harmful chemical substances. However, if a chemical substance gets into the eye, the immediate recommended action to take is to flood the eye with a Tot of low pressure water. This should be done immediately because a delay of only a few seconds might result in severe damage to the eye or even loss of vision. Flush with cold water (5 minutes or more) FIGURE 6B. GENERAL CARE FOR CHEMICAL BURNS FILL IN THE BLANK THE REMOVAL OF HARMFUL CHEMICAL SUBSTANCES FROM THE EYE IS AIDED BY THE EYE'S MOIST SURFACE AND ‘ Answer: tears 88 378 The use of water is the suggested first step in the treatment of any chemical burn. This represents the only method for limiting the severity of the burn for an individual. Remember, do not hesitate to use large quanti- ties of water; there is no such thing as using too much in such cases. FILL IN THE BLANK THE SEVERITY OF ANY CHEMICAL BURN CAN BE LIMITED BY USING LARGE AMOUNTS OF ON THE SITE OF THE INJURY. Answer: water 38B Individual differences also play a part in the case of dermatitis in that resistance to irritation varies with the individual. The following factors of susceptibility generally apply: e Lighter skinned persons are more affected by irritant chemicals than those with dark skin. e Women have a lower rate of dermatitis, possibly due to their habits of cleanliness, type of work, or the fact they are more willing to seek treatment for skin problems than men. ® A poor diet may cause sensitivity in certain individuals. eo Workers who perspire freely are more susceptible to dermatitis. eo Workers with naturally oily skin are less likely to incur dermatitis, however, this condition can actually contribute to some cases of oil dermatitis. eo Dry skin cracks easily making it more susceptible to infection. Due to the seriousness of this particular industrial problem, the recog- nition that a worker's skin disease is directly related to his occupation is the first step in the management of this most prevalent condition. FILL IN THE BLANKS RESISTANCE TO DERMATITIS VARIES WITH EACH AND THE FIRST STEP IN ITS MANAGEMENT IS OF THE PROBLEM. Answer: individual, recognition 89 39B Gases In addition to producing vapors and causing dermatitis by skin contact, certain chemicals in the form of gases can also cause an oxygen-deficient atmosphere. In this situation, the oxygen available for breathing is below the level that is considered safe for human exposure and the body is pre- vented from getting the amount of oxygen it needs to survive. Under normal conditions, air contains approximately 21 percent oxygen. Figure 7B shows the makeup of clean, dry air. Nitrogen 78.08% Argon + CO: + R), other gases 0, 0.97% Gas Symbol Volume %' Nitrogen N2 78.08 Oxygen 0: 20.95 Argon Ar 0.93 Carbon Dioxide CO: 0.03 Other? _— 0.01 1 Cubic feet of gas in 100 cubic feet of air. 2 Includes neon, helium, krypton, xenon, hydrogen, methane, nitrous oxide and ozone. FIGURE 7B. MAKEUP OF CLEAN, DRY AIR Within a mine, however, the law states the air must contain at least 19.5 percent oxygen, nor more than 0.5 percent carbon dioxide, and no harmful quantities of other noxious or poisonous gases. TRUE OR FALSE AIR CONTAINING 20 PERCENT OXYGEN IS CONSIDERED OXYGEN DEFICIENT IN AN UNDER- GROUND MINE. Answer: false 90 408 Gases are divided into four groups labeled I, II, III, and IV. The first three are all harmful and are divided according to how easy the harmful amounts can be detected by the senses. Group IV gases are not toxic, but in sufficient quantities, they cause suffocation by replacing oxygen in the air. This type of hazard is created for example by nitrogen, a gas which is not in itself harmful or irritating. In some cases such as surging a tank, the nitrogen can become so abundant in the surrounding atmosphere that it replaces the oxygen which is necessary for breathing. A worker in such an atmosphere can rapidly suffocate and die. The gases which present such hazards are called asphyxiating gases. Some of these are listed below. In high concen- trations, some of these gases are also flammable and those are indicated with an asterisk. Acetylene* Hydrogen* Argon Methane* Butane* Neon Carbon Dioxide Nitrogen Ethane* Nitrous Oxide Ethylene* Propane* Helium FILL IN THE BLANK CARBON DIOXIDE, HYDROGEN, AND NITROGEN ARE GASES THAT CAN CAUSE SUFFOCATION AND DEATH BY PREVENTING ENOUGH OXYGEN FROM BEING IN THE AIR AND THESE HAZARD- OUS GASES ARE CALLED GASES. Answer: asphyxiating 418 Physically, the first signs of oxygen deficiency an individual will notice are increased rate and depth of breathing. If an individual is in an atmosphere where there is Tess than 16 percent oxygen, dizziness, rapid heartbeat, and headache will also be noticed. Oxygen-deficient atmospheres also hinder an individual's movement and can cause a semi-conscious lack of concern about the possibility of death. It is obvious for the reasons men- tioned that a worker should not knowingly enter areas of oxygen deficiency without an emergency air supply. 91 41B CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING ARE PHYSICAL SYMPTOMS OF A LACK OF SUFFICIENT OXYGEN? A. INCREASED BREATHING AND HEART RATE B. DIZZINESS AND HEADACHE C. HINDRANCE OF MOVEMENT D. BOTH A AND C E. ALL THE ABOVE Answer: E 428 When an individual suddenly enters an area containing little or no oxy- gen, the person usually will not experience any warning symptoms, but will immediately lose consciousness. If the victim is fortunate enough to be rescued and revived, there will probably be no memory of the incident. The senses, therefore, cannot be counted on as an alarm telling a person of an oxygen-deficient atmosphere. This type situation is a definite threat to any miner. Oxygen-deficient atmospheres can and do exist in mine areas where the air is diluted or displaced by gases or vapors or where oxygen is consumed by chemical or perhaps biological reactions. FILL IN THE BLANKS AN INDIVIDUAL'S CANNOT BE RELIED UPON AS AN WARNING AGAINST OXYGEN-DEFICIENT ATMOSPHERE AND AS A RESULT, UPON SUDDEN ENTRY INTO SUCH AN AREA, A PERSON WILL USUALLY LOSE i Answer: senses, alarm, consciousness 43B Gases, instead of creating an oxygen-deficient atmosphere, can also be a harmful contaminant to the body. These gases are classified as type I, II, or III. Breathing of these gases may cause irritation to the eyes, nose, throat, upper respiratory tract, lung tissue, or even the deep passages of the lung, the air sacs. The possibility of damage depends on the solubility 92 43B of the irritant gas in water or how easily it can be dissolved. The more soluble the gas in water, the more quickly it will dissolve in the watery passages of the breathing tubes resulting in damage to the upper respiratory system (example - sulfur dioxide). Insoluble gases, or those that are not easily dissolved, have the capability of being breathed in all the way past the air tubes and reach the air sacs where they cause a severe reaction and damage (example - nitrogen dioxide). FILL IN THE BLANK GASES CAN CAUSE IRRITATION AND OR DAMAGE TO THE UPPER RESPIRATORY TRACT, THE AIR SACS, AND EVEN OTHER PARTS OF THE BODY, BUT THE GASES WILL DETERMINE THE SEVERITY AND SITE OF DAMAGE. Answer: solubility 448 Group I gases will make the eyes, nose, and throat sting if they are present at levels near or above the TLV. Ammonia is an example of a gas in Group I. In the case of ammonia, if enough of this gas is present in the air causing a worker's eyes, nose, and throat to sting, inhalation is hazard- ous. Workers in this situation should immediately leave the area and report the situation. FILL IN THE BLANKS GROUP I GASES WILL CAUSE AN INDIVIDUAL'S NOSE, THROAT, AND EYES TO AND IF THIS OCCURS, THE PERSON SHOULD THE AREA IMMEDIATELY AND REPORT THE SITUATION. Answer: sting, leave 458 Irritation as the result of group II gases is relatively mild so notic- able irritation is not a good indication of whether the exposure level is safe. An example of a group II gas is nitrogen dioxide. This gas is gener- ated by the burning or setting of explosives and if breathed in, produces an adverse reaction in the tissues of the lungs. 93 468 Inhalation of nitrogen dioxide gas, for example, causes a chemical burn to the mucous membranes of the lungs. The nitrogen dioxide reacts with the watery atmosphere of the respiratory tract and air sacs producing nitric acid. In response to this reaction, an acid burn results, causing a release of fluid from the injured tissue. Pulmonary edema (swelling caused by the release of fluid) then occurs interfering with an individual's oxygen exchange. This can cause suffoca- tion of the victim. Symptoms of pulmonary edema are weakness, cold sweat, nausea, cough with frothy yellow-brown sputum, severe shortness of breath, need for air, and anxiety. Also, recent studies tend to indicate that nitro- gen dioxide may speed up the onset of Tung cancer and other diseases. FILL IN THE BLANKS NITROGEN DIOXIDE IS AN EXAMPLE OF A GROUP GAS AND A GAS SUCH AS THIS PRODUCES AN ADVERSE REACTION IN THE OF THE LUNGS. Answer: II, tissues 478 The most dangerous gases are those found in group III. These gases can be present at levels above the TLV, and even cause death, before giving any warning signs of irritation or odor to an individual. An example of a gas in this group is carbon monoxide. Carbon monoxide is an odorless, colorless, and tasteless gas and as a result, its presence is difficult to detect. It is produced by the incom- plete burning of fuels that contain carbon such as coal, wood, paper, oil, natural gas, and gasoline. Carbon monoxide is especially common where vehicles are operated in an enclosed area. This particular gas replaces oxy- gen in the blood thus interfering with the normal oxygen transfer, causing oxygen starvation to the body within minutes. Its effect, however, does depend on the quantity of gas and length of exposure. 48B Symptoms of carbon monoxide poisoning include tightness across the fore- head, headaches, throbbing in the temples, sleepiness, weakness, rapid breathing, dizziness, nausea, and vomiting. Workers should be familiar with the danger resulting from carbon monoxide, so that if any of the symptoms above are experienced, they can quickly get fresh air and have the job site checked. 94 488 FILL IN THE BLANKS GROUP III GASES ARE CONSIDERED TO BE THE MOST BECAUSE THEY CAN CAUSE BEFORE GIVING ANY WARNING SIGNS OF THEIR PRESENCE. Answer: dangerous, death 498 There are times in the mining industry when various producers of these hazards can and do occur at the same time. For example, explosives, welding operations, and diesel engines release oxides of nitrogen. These nitrogen oxides irritate the eyes as well as the upper respiratory tract. Cough and chest pains are immediate results of exposure to levels above the threshold limit. In the mining industry, as an example, nitrogen oxides also act to impair the bronchial clearance mechanisms, so that dust, created from blast- ing, is not efficiently cleansed from the Tungs. As a result, several harm- ful effects occur to the respiratory system. TRUE OR FALSE VARIOUS LUNG HAZARDS CAN OCCUR AT THE SAME TIME IN CERTAIN MINING OPERATIONS. Answer: true 50B Dusts Physically, certain reactions will occur to the body as a result of the inhalation of airborne substances. These reactions, however, will vary de- pending on the type of contaminant, how harmful it is, how much is inhaled, length of exposure, where the contaminant ends up on the body, and how long it remains there. Such reactions would include: e Cardiopulmonary reactions such as silicosis, asbestosis, and coal workers' pneumoconiosis. eo Systemic reactions caused by harmful dusts from such elements as lead. ® Metal fume fever resulting from the inhalation of fine and freshly generated fumes of zinc or magnesium or of their oxides. 95 50B eo Allergic reactions caused by inhalation or possible skin contact with organic dust as well as organic and inorganic chemicals. eo Irritation of the nose and throat caused by acid, alkali, dust, or mists. eo Damage to internal tissue resulting from inhaled radioactive materials emitting ionizing radiation. FILL IN THE BLANKS THE INHALATION OF AIRBORNE SUBSTANCES WILL CAUSE CERTAIN REAC- TIONS TO THE BODY THAT WILL DEPENDING ON SEVERAL DETERMINANTS. Answer: physical, vary 51B The inhalation of substances in the work area is second only to derma- titis as being the cause for most occupational diseases. Dust that occurs in the workplace vary greatly in size ranging from 0.1 to 25 microns and the smaller particles tend to outnumber the larger ones. Remember, it is respir- able dust, those particles that reach the lungs, that causes the most health problems. Respirable dusts that reach the lungs can either pass directly into the bloodstream and be absorbed or they may stay in the lungs and cause damage. Consequently, if dust is visible in the air around a work area, chances are that there are more invisible than visible dust particles present. FILL IN THE BLANKS INHALATION OF DUST CAUSES A GREAT NUMBER OF OCCUPATIONAL DISEASES, THEREFORE, DUST IN THE WORKPLACE SHOULD INDICATE TO THE WORKER THE PRESENCE OF DUST. Answer: respirable, visible, invisible 52B Recognition of dust exposure depends on a knowledge of the chemical makeup of the dust, its size and concentration, and how it is dispersed. Settling time is an important factor because in order for dust exposure to occur, the particles have to be in the air. Settling time varies with a 96 52B particle's size, density, and shape. Particles larger than 10 microns settle quickly. Respirable particles, however, settle more slowly. For example, silica dust five microns in size takes about two and one-half minutes to settle, while silica dust 0.25 microns in size takes about 10 hours to settle. FILL IN THE BLANKS SETTLING TIME VARIES DEPENDING ON PARTICLE > > AND SHAPE. Answer: size, density 53B Lung disease caused by respirable dust is called pneumoconiosis. This, term comes from the Greek pneumo - meaning lung, coni - meaning dust, and 0sis - meaning reaction. Respirable dusts which cause lung disease include, for example, silica, coal, and asbestos fibers. These dust particles must usually be smaller than five microns in order to enter the lungs, with the exception of fibrous materials such as asbestos and talc. CIRCLE THE CORRECT ANSWER PNEUMOCONIOSIS IS A LUNG DISEASE CAUSED BY RESPIRABLE A. DUST B. FUMES C. MIST D. ALL THE ABOVE Answer: A 54B Silicosis, a disease which cripples the lungs, is most often found in non-coal mining environments. The scarring of the lungs that results is caused by the inhalation of fine respirable silicon dioxide dust. This di- sease may develop either slowly (chronic) or quickly (acute) in its victims. Miners who are exposed to large amounts of very finely divided dust particles of silica are most likely to become victims of the fast-developing type. 97 55B Symptoms of rapid-developing or acute silicosis may appear as early as 8 to 18 months after exposure. Shortness of breath is the primary symptom. In the early stages, the victim will be short of breath during physical activity, but this will increase to where it occurs after less and less exer- tion. Eventually, the condition will advance to the point where the victim is short of breath even while resting. This is caused by the presence of many small round lung scars which are the result of irritation by silica dust. The presence of these scars makes the lungs stiff, requiring more effort to inflate them with air. The walls of the air sacs are also thickened by the scars, blocking the transfer of oxygen into the blood. Thus, low oxygen con- tent in the blood is a characteristic of silicosis. The scars can also join together into larger scars by further reaction to the silica. Some may even occupy an entire lung. This process is called progressive massive fibrosis, and is often accompanied by increased susceptibility to tuberculosis and other infections. As a result, the heart becomes weakened and enlarged by the strain of having to pump more blood to provide the body with a sufficient supply of oxygen. The development of chronic silicosis is very similar to that of acute silicosis, with the exception of the speed at which it occurs. It may slowly appear after several years of exposure and many more years may pass before it becomes worse. FILL IN THE BLANKS LUNG SCARRING CAUSED BY INHALING THE FREE, FINELY DIVIDED DUST OF SILICA IN A MINE MAY CAUSE , THE PRIMARY SYMPTOM OF WHICH IS Answer: silicosis, shortness of breath 56B Coal workers' pneumoconiosis (black lung) is caused by exposure to the dust of soft (bituminous) coal, which may contain small amounts of silica. Large quantities of this respirable black dust are deposited in the lungs, particularly at the end of the small air tubes just before they enter the air sacs. Due to this peculiar location and the properties of the dust itself, the disease has the characteristics of bronchitis and emphysema as well as those of silicosis. Like silicosis, it leads to scarring of the lungs, which results in stiffening of the lungs and possibly in heart strain. Hard coal, or anthracite, contains enough silica to cause a lung disease more like silicosis and can cause scars large enough to occupy almost the whole lung. X-rays can detect this disease relatively early; however, the symptoms of respiratory disease usually appear only after several years. 98 57B When the small scars of simple coal workers' pneumoconiosis join together to make large masses of scar tissues, complicated pneumoconiosis results. These stony hard masses may occupy more than one-half of the Tung. As the scars pull together, the air sac walls behind them tear, causing severe em- physema. Black lung may be complicated, often fatally, by respiratory infec- tions, especially tuberculosis. Cigarette smoking seems to have the effect of making cases of black Tung more frequent and more severe among workers who are exposed to coal dust. Although it was formerly believed by doctors that the amount of Tung scarring or disease resulting from coal dust was dependent upon the exact amount of silica contained in the dust, sufficient information has now been collected to indicate that silica-free coal has the ability to produce small scars as well as large ones. FILL IN THE BLANKS MINERS WORKING IN SOFT AND HARD COAL ARE EXPOSED TO LEVELS OF RESPIRABLE DUST WHICH CAN CAUSE THAT CAN BE EITHER OR Answer: pneumoconiosis, simple, complicated 58B Asbestos is a fibrous mineral whose fibrous strings are very strong. Being heatproof, fireproof, and resistant to most chemicals, it is used in more than 3,000 products, from potholders and children's toys to welding rods and industrial and household insulation. It is present in some form in many factories and homes. For this reason, almost no person is without potential exposure. Asbestos fibers are extremely fine. They are so fine that one million of them can occupy an inch as compared to approximately 630 human hairs. Because of their very small size, when these fibers are airborne they float like water vapor and do not settle easily. Because they are not trapped by the mucus or hairs of the nose or air passage and are respirable, they can enter the air sacs of the lungs without any trouble causing the disease asbestosis. It is estimated that during an 8-hour shift, at the legal limit of two fibers per cubic centimeter of air, a worker could breathe 15 million fibers, many of which will remain trapped in the lungs. They remain just as indestructible insite the body as they were on the outside. If at the age of 18 a worker breathes in asbestos fibers, chances are these same fibers will still be in the lungs at death. 99 59B The body tries hard to isolate asbestos fibers which it cannot destroy. Individual fibers or groups of fibers may, over a period of 10 to 20 years, become surrounded with a thick wall of scar tissue. This scar tissue causes the lungs to lose their ability to expand and contract. The lungs also be- come hard and smaller than usual. As a result, the lungs hold less air and it becomes harder for the heart to pump blood through them. This makes the transfer of oxygen to the bloodstream difficult. Respiratory infections also become a constant threat to persons with asbestosis, because even minor in- fections can cause severe shortness of breath and possibly death. Also, the frequency and severity of asbestosis seems to be increased by cigarette smoking. CIRCLE THE CORRECT ANSWER THE BODY CANNOT DESTROY ASBESTOS FIBERS AND AS A RESULT A. SCAR TISSUE WILL FORM IN THE LUNGS B. THE TRANSFER OF OXYGEN BECOMES DIFFICULT C. RESPIRATORY INFECTIONS BECOME A THREAT D. BOTH A AND C E. ALL THE ABOVE An even more serious effect of asbestos dust is its ability to cause body cells to become cancerous. Scientists are confused as to why this change occurs. It is possible that the reason may be the long period of time that asbestos dust remains in the lungs, or possibly it is the ability of asbestos to absorb other harmful chemicals onto its surface. Perhaps the surface of the asbestos fibers may hold carcinogenic (cancer-producing) chemicals in contact with the body cells and after years of remaining in contact with the carcinogenic chemicals, the cells become malignant (cancer- ous). However, it is only after a period of 20 to 30 years that workers develop such cancer. 100 61B Talc is also an extremely fine dust and, as is the case with asbestos, the smaller particles are the most dangerous to the body. Once these respir- able particles of talc reach the lungs, the body is unable to remove them. The lung scarring that results is a lot like that of asbestosis in that the major effects of talc exposure also usually appear after 20 to 30 years. FILL IN THE BLANKS ASBESTOS AND TALC ARE SIMILAR IN THAT THEY GENERATE Answer: fine dust 62B There are also radioactive dusts and nuisance dusts. Radioactive con- taminants can actually be taken into the body as either a gas, dust, fume, or mist. Once inside the body, these contaminants may be deposited in various organs creating a source of internal radiation. Nuisance dusts on the other hand do not cause lung damage, disease, or harmful effects to the body under normal circumstances. They can, however, if present, cause: a possible reduction in visibility; an unpleasant deposit in the eyes, ears, or nose; or an irritation of the nose, throat, or skin. This occurs because the dust is gritty or because its removal requires hard scrubbing. Also, it should be kept in mind that certain dust, now considered only nuisance dust, may in the future be considered a health hazard. For this reason, any dust continually present in a workplace should be controlled as much as possible to protect the worker's health and well-being. FILL IN THE BLANKS RADIOACTIVE DUST, ONCE IN THE BODY, CREATES A SOURCE OF HARMFUL , WHILE DUSTS DO NOT USUALLY CAUSE DAMAGE TO THE BODY. Answer: internal radiation, nuisance 63B Fumes Dusts that have a harmful effect on body functions are caused mainly by metal dusts and fumes. It seems that all metal fumes are irritating, specif- ically when they are freshly produced. Fumes are especially dangerous to an individual because their particles are very fine and as a result can be breathed deep into the respiratory system. The most common hazardous metals found on the job are lead, mercury, beryllium, chromium, cadmium, and manganese. 101 64B Fumes, remember, are very fine,solid particles that arise from heating solids such as lead. Fumes are not odorous gases and vapors! When a metal is heated to a high enough temperature, it is vaporized (changed to a gaseous state). This vapor cools shortly and condenses to form extremely fine, solid particles which usually combine with oxygen in the air to form metal oxides. The metal oxide clouds in the air are called fumes. FILL IN THE BLANK METALS SUCH AS LEAD CAN HAVE A HARMFUL EFFECT ON THE BODY CAUSED MAINLY BY DUST AND Answer: fumes 658 Lead, for example, can enter the body by ingestion and inhalation. Or- ganic lead compound can enter the body by absorption. Once in the body, lead can cause harmful effects to an individual's gastrointestinal, blood, and central nervous system. Swallowing of lead can be a problem or add to an existing problem if personal hygiene is poor in the workplace. Inhalation, however, is the most common route of entry for lead. Although the body can take care of and eliminate small amounts of lead, if intake is more than elimination, a harmful buildup occurs in the body. If exposure to lead continues over a period of years, poisoning can cause death. FILL IN THE BLANKS LEAD'S MOST COMMON ROUTE OF ENTRY IS AND IF EXPOSURE TO THE BODY CONTINUES OVER A PERIOD OF YEARS, LEAD POISONING CAN BE . Answer: inhalation, fatal 668 Beryllium dust or fumes on the other hand causes disease of the lungs, skin, Tiver, and kidneys. Of these diseases, however, the effects on the lungs are the most noticeable and disabling. Brief, intensive exposure, or extended exposure to low concentrations of these dusts or fumes can cause acute berylliosis, a severe, pneumonia-like condition of the Tungs. Individ- ual susceptibility determines what degree of exposure will cause this disease; 102 66B it may in fact be caused by an extremely low amount of exposure in some persons. The symptoms which are typical of this disease are: cough with phlegm (which may contain blood), severe shortness of breath, and loss of weight over the first few weeks. Although the victim is seriously ill, chest X-rays may be normal at first. Oxygen transfer into the blood may be blocked if the lung inflammation is severe. This disease is often fatal but the victim who does recover most likely will have permanent damage to the Tungs. 67B After a period of exposure from 1 to 20 years, the worker may develop chronic berylliosis. Abnormalities, however, may appear on X-rays many years before symptoms appear. The symptoms may be initially mild, progressing slowly to a more severe and disabling illness. The chronic inflammation causes the lungs to become stiff and unable to transfer oxygen to the blood- stream. After years of overworking in order to pump blood through the inef- ficient lungs, the heart becomes enlarged, leading to eventual heart failure. FILL IN THE BLANKS A SEVERE PNEUMONIA-LIKE INFLAMMATION OF THE LUNGS CAUSED BY AN INTENSIVE OR EXTENDED EXPOSURE TO LOW CONCENTRATIONS OF BERYLLIUM IS CALLED , HOWEVER, AFTER EXPOSURE FOR A PERIOD OF 1 TO 20 YEARS MAY DEVELOP. Answer: acute berylliosis, chronic berylliosis 68B Fumes are also produced during welding from the vaporization of the metal or compound in the area of the arc. A fume can also be formed when materials such as magnesium metal is burned or when welding or gas cutting is done on galvanized metal. There are also many instances where hot welding vapors react with the air to form oxides. Lead oxide fumes, for example, are produced during smelting and iron oxide fumes are given off in the course of arc welding. These oxides do affect the Tungs but not all oxides are dis- abling. The degree to which fumes evolve and are produced depends on the weld- ing process, the composition of the filler metal, the flux coating or shield- ing gas, the electrode coating and the composition of the material being welded. The presence of corrosion products, oil, grease, paint metallic coat- ings, or process chemicals will vary the composition of the fumes. 103 63B FILL IN THE BLANK DURING THE WELDING PROCESS, VAPORIZATION OF THE METAL IN THE AREA OF THE ARC PRODUCES . Answer: fumes 69B The effects of some metal fumes appear to be temporary. Metal fume fever is a condition that lasts only a few hours to several days. It is caused by a brief, high exposure to freshly generated metal fumes such as zinc, magnesium, or their oxides. Usually, the symptoms appear within 4 to 12 hours after exposure. New workers are susceptible during the first few days of work and older workers who have been away from the job may de- velop the reaction. Typical symptoms are chills and fever, nausea, vomiting, body aches, and heavy perspiration. Complete recovery is usually made within a day and artificial immunity is commonly developed after one or two fevers. This immunity will disappear in about five days if there is no contact with the fume within that time (examples: vacation, layoffs, strikes). The primary treatment for metal fume fever is prevention. Apparently, the fever is caused only from the inhalation of extremely fine particles, freshly formed as fume. Adequate ventilation is therefore the principal means of prevention of metal fume fever. FILL IN THE BLANKS SHORT EXPOSURE TO A LARGE AMOUNT OF RECENTLY PRODUCED METAL FUMES CAN CAUSE AND THE BEST WAY TO TREAT THIS CONDITION IS Answer: metal fume fever, prevention 70B Mists Unlike fumes, mists are formed when finely divided liquids are suspended in the air. If inhaled, harmful mists, found wherever corrosive liquids are sprayed, bubbled, splashed, or foamed, can severely irritate the nose, throat, and lungs. For example, the steam from a degreasing tank can carry a mist that is harmful if inhaled. The use of solvents and spray painting are other situations in which hazardous mists can occur. 104 70B TRUE OR FALSE MISTS DIFFER FROM FUMES IN THE SIZE OF PARTICLES THAT ARE SUSPENDED IN THE AIR. 71B 0i1 mists also occur in industry when mineral oils are sprayed on metal as machine aids and coolants. When used for this purpose, the heat that is produced from the work process breaks down the oil mist which may cause an irritation to the lungs if inhaled. In high concentrations, these oil mists might cause a form of pneumonia and lung scarring. It is hard to detect oil in the air, but generally if the air feels oily, conditions are hazardous. 72B It is obvious, therefore, that workers who work around corrosive liquids check for any burning sensation when they first enter their work area. This is important because after continuous exposure, dangerous exposures tc mists may go unnoticed. TRUE OR FALSE MISTS ARE FORMED FROM EITHER FINELY DIVIDED LIQUIDS OR SOLIDS AND AS A RESULT HARMFUL MIST CONDITIONS CANNOT BE DETECTED BY A WORKER IN THE WORKPLACE. LET'S PAUSE NOW AND REVIEW THE RECOGNITION OF CHEMICAL STRESS. 1. TO COMPLETE A JOB SAFELY USING SOLVENTS DEPENDS ON A. PROPER SELECTION D. PROPER LABELING B. PROPER HANDLING E. ALL THE ABOVE C. PROPER CONTROL 105 10. 11. 12. 13. 73B THE METHODS OF SOLVENT EXPOSURE THAT PRODUCE THE GREATER PHYSICAL EFFECT ON THE BODY ARE AND . THE MAIN CAUSE OF OCCUPATIONAL DERMATITIS IS FROM EXPOSURE. INDIRECT FACTORS THAT CONTRIBUTE TO DERMATITIS ARE AND PRE-EXISTING RESISTANCE TO DERMATITIS VARIES WITH THE INDIVIDUAL, THUS MAKING AN IMPORTANT FACTOR WHEN CONSIDERING DERMATITIS. GASES ARE DIVIDED INTO FOUR GROUPS AND BASICALLY CAN EITHER BE OR CAUSE _ BY REPLACING OXYGEN IN THE AIR. UPON ENTERING AN OXYGEN-DEFICIENT AREA, A PERSON USUALLY WILL NOT HAVE ANY WARNING BUT WILL IMMEDIATELY : GASES THAT IRRITATE A PERSON'S EYES, NOSE, THROAT, UPPER RESPIRATORY TRACT, LUNG TISSUE, AND AIR SACS ARE FOUND IN GROUPS A. 1, 11 B. “I, 111 C. ‘1s 11, 111 D. NONE OF THE ABOVE THE MOST DANGEROUS GASES ARE FOUND IN GROUP SOLUBLE GASES TEND TO AFFECT THE AND GASES TEND TO AFFECT THE AIR SACS. SECOND ONLY TO DERMATITIS AS THE LEADING CAUSE OF OCCUPATIONAL DISEASE 1s OF HARMFUL SUBSTANCES. WHICH OF THE FOLLOWING DUST SAMPLES WOULD SETTLE FIRST? A. .75 MICRONS OF COAL DUST B. 5.0 MICRONS OF TALC C. .33 MICRONS OF SILICA D. 1.0 MICRONS OF NUISANCE DUST PNEUMOCONIOSIS IS A LUNG DISEASE CAUSED BY THE INHALATION OF RESPIRABLE 106 73B 14. GAS-LIKE EMISSIONS CONTAINING VERY SMALL, SOLID PARTICLES THAT CAN BE BREATHED INTO THE LUNGS ARE CALLED AND THEY ARE DANGEROUS AND IRRITATING WHEN THEY ARE GENERATED AND INHALED. 15. WHEN CORROSIVE LIQUIDS ARE USED ON THE JOB, THERE IS ALWAYS THE POSSI- BILITY OF FINDING FINELY DIVIDED LIQUIDS SUSPENDED IN THE AIR CALLED Answers: 1. E 9. III 2. skin contact, inhalation 10. upper respiratory system, 3. chemical insoluble 4. personal hygiene, skin 11. inhalation diseases 12. -B 5. individual differences 13. dust 6. toxic, suffocation 14. fumes 7. lose consciousness 15. mists 8. C If the correct answers to these questions were not clear, review before moving ahead. The next area of this section deals with recognizing physical hazards. 748 Physical Hazards A second category of industrial dangers is physical hazards. A good example of this type of hazard is noise. Noise is very noticeable and over time can seriously affect you. Physical hazards can have either an immediate or long-term effect on a worker's health and safety. These hazards are, therefore, just as important as chemical hazards. FILL IN THE BLANKS PHYSICAL HAZARDS CAN HAVE EITHER AN OR EFFECT ON YOUR HEALTH. Answer: immediate, long-term 107 75B Noise and Vibration We are all constantly exposed to noise (unwanted sound) especially while at work in an industrial environment. In industry, noise in many cases is accompanied by vibration. This double exposure to both noise and vibration can be especially harmful to the human body. Exposure to the combination of jolting and excessive noise, even in small amounts, is uncomfortable and ex- posure may lead to irritation and the inability to concentrate, resulting in an increase in accidents. FILL IN THE BLANK DOUBLE EXPOSURE TO BOTH UNWANTED SOUND AND CAN BE HARMFUL TO THE HUMAN BODY. Answer: vibration 76B Sound travels through the air in the form of waves which are similar to those formed by a fish jumping in a pond or by throwing a rock into a pool of water. The larger the stone or fish, the larger and more far reaching are the waves. The same is true of sound waves. These sound waves have the characteristic of frequency (highness and lowness of sound) and Hertz (cycles per second) is the unit used to measure frequency. Ne Aa 2 Uy ov 7 OEE Tho XS 4) ——— TT i FIGURE 8B. SOUND WAVES FILL IN THE BLANKS SOUND TRAVELS THROUGH THE AIR IN WHICH HAVE THE CHARACTERISTICS OF Answer: waves, frequency 108 778 The intensity of sound is the pressure that is made when sound is pro- duced. "Loud" noises are noises with lots of pressure, while "soft" noises are noises with little pressure. Sound pressure is expressed in units called decibels. Figure 9B shows some examples of noise levels that may be of in- terest to you. Conversation Alarm clock Coal drill Roof bolter Shuttle car Crane and shovels ‘Mantrips Loaders Continuous miner Car horn Rock band Jet engine daBa 50 60 70 80 90 100 Ho 120 130 Levels FIGURE 9B. NOISE LEVELS You will notice that sounds produced by an active rock band, a large jet motor, and a pneumatic hammer have the highest dBA rating. That means the sounds made by these things have the highest intensity. To you this would mean they are the noisiest. Sound then has the characteristics of both frequency and intensity. FILL IN THE BLANK SOUND PRESSURE IS EXPRESSED IN UNITS CALLED Answer: decibels 109 78B The ear can be expected to do its job for a lifetime with only aradual hearing loss due to old age (presbycusis). The modern industrial environ- ment, however, can sometimes present more abuse to the human ear than it can cope with. FIGURE 10B. HEARING DAMAGE The body reacts with shock in the form of tension, stress, and anxiety to Toud noise. As a result an individual's blood pressure goes up in the presence of loud noise. Noise also interferes with voice instruction and signals, thus hindering communication. Noise can also put enough strain on the nerves of the inner ear to cause a temporary hearing loss. Finally, extremely loud and sudden noise can actu- ally break the eardrum. However, the factors that relate to the amount of hearing loss are the type of noise, its intensity, and a person's length of exposure. Overexposure, however, is the major cause of hearing problems. CIRCLE THE CORRECT ANSWER A FACTOR THAT DOES NOT RELATE TO THE AMOUNT OF HEARING LOSS IS A. LENGTH OF EXPOSURE B. NOISE INTENSITY C. TYPE OF NOISE D. SIZE OF EARDRUM E. NONE OF THE ABOVE 110 79B Without a break from continuous exposure to noisy conditions, a tempo- rary hearing loss can become permanent after several years. In fact, workers employed in noisy industrial occupations such a mining are suffering permanent hearing loss. However, if your job causes you, on occasion, to enter and leave the noisy work environment during work, it will probably take twice as long for a hearing Toss to occur. COMPLETE THE SENTENCE WITHOUT A BREAK FROM CONTINUOUS NOISE, A MINER'S TEMPORARY HEARING LOSS CAN Answer: become permanent after several years 80B Noise that stops and starts (intermittent) at different times must be recognized as different from continuous, impact, and impulse noise. Inter- mittent noise is not continuous and its Tevel of sound pressure changes slowly. 81B A continuous noise, for example, is one that you might hear all day long at the workplace. This could be something like the noise that a preparation plant makes. In continuous noise, the sound intensity level tends to remain pretty much the same all the time. Impact noise is the kind of noise you hear when someone slams a car door or when someone strikes metal with a hammer. The sound intensity varies greatly in impact noises. The kind of noise that is made when explosives are set off or when a gun is fired is called impulsive noise. Figure 11B illustrates these types of noise. 81B IMPULSIVE IMPACT NOISE ~ FIGURE 11B. TYPES OF NOISE Workers exposed to impact and impulse noise do suffer hearing loss. However, we do not know whether the loss is equal to, greater than, or less than the hearing Toss from steady noise. FILL IN THE BLANKS FOUR DIFFERENT TYPES OF NOISE ARE ’ > » AND . Answer: continuous, intermittent, impact, impulsive 82B The physical hazard associated with noise that also presents a problem is vibration. These vibrations are measured in cycles per second. When standing or sitting on a vibrating surface or holding a vibrating tool, vibrations are transmitted to your body. Broad vibrations, those Tess than three cycles per second, can cause the whole body to move. This may induce motion sickness. 112 83B Vibrations of four to 12 cycles per second caused, for example, by a rock drill can, depending on their direction and the position of the affected person, cause hips, shoulders, and abdominal parts to move. These vibrations are transmitted to the bones and joints and cause alternating movement of the bone ends against the smooth material of joint surfaces (cartilage). As a result, both skeletal and muscular systems, as well as some living cartilage cells, may be damaged or destroyed. The affected area may also become in- flamed, causing increased damage and repeated exposures can lead to arthritis. FILL IN THE BLANKS BROAD VIBRATIONS CAN CAUSE SICKNESS AND REPEATED EXPOSURE TO FASTER VIBRATIONS OF FOUR TO 12 CYCLES PER SECOND CAN CAUSE THE y » AND ABDOMINAL PARTS TO MOVE. Answer: motion, hips, shoulders 848 Vibrations of four to five cycles per second affect the joints of the backbone and also cause the organs of the abdomen to vibrate. Stomach and digestive problems can therefore become a problem among workers exposed to these vibrations. Riding on certain equipment can cause such vibrations. The most serious vibrations, however, are those of 20-30 cycles per second. Such vibrations actually vibrate the skull and can cause loss of vision. If sufficiently intense, your whole body vibrates and permanent physical injury can result. However, vibrations this severe are not common in the mining industry. FILL IN THE BLANKS VIBRATIONS OF FOUR TO FIVE CYCLES PER SECOND NOT ONLY CAN DAMAGE THE JOINTS OF THE BACKBONE, BUT CAN ALSO CAUSE AND PROBLEMS. LOSS OF VISION CAN BE CAUSED BY VIBRATIONS OF CYCLES PER SECOND. Answer: stomach, digestive; 20-30 113 85B Temperature and Pressure Other physical stresses common in the work environment are temperature and pressure extremes. During surface mining, and in some underground mines, varying temperature and pressures exist that can have an effect on an individ- ual's work and perhaps his health. For example, in an experiment, a number of miners were loading mine cars in a moisture-saturated worksite at various environmental temperatures. The work output of miners dropped from 100 to 20 percent as the air temperature was raised from 8COF to 950F. WERE FVERSY 80°F TEER ITRoOwwW 89°F HRT EE II ATTA 91.5°F SES ETI HTT ESE 94°F SS SETS SE ETER 95°F FIGURE 12B. WORK OUTPUT 868 In order to maintain a constant internal temperature, your body has cer- tain heating and cooling mechanisms. These mechanisms can cope with a limited range of environmental temperatures. The range of comfortable tem- peratures is narrow and varies greatly depending on your level of activity, the humidity, and air movement. Humidity, or the amount of moisture in the air, along with air movement, relate to bodily comfort in that they affect 114 868 the rate at which the body loses heat. Lower temperatures are preferred for more active work because body activity generates heat. However, temperature extremes, either high or low, can result in life threatening conditions. FILL IN THE BLANKS AN INDIVIDUAL'S LEVEL OF ACTIVITY, THE HUMIDITY, AND AIR MOVEMENT ALL AFFECT THE RANGE OF Answer: “comfortable temperatures 87B In the mining industry, you may work in areas that are too warm. Let's look at how your body adjusts to heat. Heat is naturally produced within the body. The body then either loses heat to the environment or gains heat from the environment. The three main ways that heat is Tost from the body is through convection, radiation, and evaporation. FILL IN THE BLANKS ALTHOUGH HEAT IS NATURALLY PRODUCED BY THE BODY, HEAT CAN EITHER BE TO THE ENVIRONMENT OR ADDITIONAL HEAT CAN BE FROM THE ENVIRON- MENT. Answer: lost, gained 88B Convection means that the warm heat produced by your body will flow away toward areas of lower temperature. The body also receives radiant heat from the sun which is absorbed by the skin. When heated, the skin will give off a large amount of radiant energy. Your body's most efficient method of heat loss however is evaporation. When water is heated, the heat energy transforms it into water vapor. As sweat turns to vapor, it removes heat from the skin thus leaving the skin cooler. 115 88B CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING REPRESENTS THE BODY'S BEST WAY OF GETTING RID OF HEAT? A. EVAPORATION B. RADIATION C. CONVECTION D. INFILTRATION Answer: A - 898 Another bodily reaction that helps an individual get used to the heat in a new environment is the process of acclimatization. This process helps the body make certain adjustments in order to maintain normal temperature (98.6O9F) when exposure to heat is more continuous. Acclimatization usually takes 4 to 6 days and it occurs most easily in young people. However, an individual's acclimatization is Tost when their exposure to heat is discontinued. Upon entering a hot environment again, an individual has to go through another acclimatization process. FILL IN THE BLANK A MINER WHO IS NOT USED TO WORKING IN A HOT ENVIRONMENT IS ABLE TO GET USED TO MORE CONTINUOUS HEAT BY THE PROCESS OF . Answer: acclimatization 908B Changes in the circulatory system also help cool your body. Small blood vessels near the surface of your body enlarge (dilate), bringing more of the "hot blood" near the skin, allowing some heat to return to the environment. Dilation of these blood vessels makes the heart work harder because of the enlarged circulation area. To compensate, blood vessels to internal organs such as the Tiver, stomach, and intestines shrink. Damage to these organs may result if they are deprived of sufficient blood for an extended period of time. 116 908B FILL IN THE BLANK LOSS OF HEAT FROM YOUR BODY CAN BE INCREASED BY THE OF BLOOD VESSELS NEAR THE SKIN SURFACE. Answer: enlargement 91B If these heat control mechanisms fail, one of several types of heat re- actions may occur. The type and severity of the reaction depends on: (1) the conditions of exposure, (2) the degree of your activity, and (3) the individual way your body responds. COMPLETE THE FOLLOWING SENTENCE WHEN A HEAT REACTION OCCURS, THE THREE THINGS DETERMINING ITS TYPE AND SEVERITY ARE > > AND ‘ Answer: conditions of exposure, degree of activity, individual response 92B Heat stroke, sometimes called sun stroke, is the most serious of the heat reactions. People who are not acclimatized and are moderately active in hot environments can develop heat stroke. This condition causes a sharp rise in body temperature, confusion, angry behavior, and even convulsions. Symptoms of the condition are warm dry skin with the absence of sweating, severe headache, visual disturbance, increased body temperature, and eventual loss of consciousness. Since heat stroke can be fatal, the victim should be sponged down or given a cold bath as soon as possible and then treated in a hospital. This condition may also be accompanied by prickly heat or heat rash. This rash indicates that an individual has an inflammation as a result of poorly functioning sweat glands. FILL IN THE BLANK THE MOST SERIOUS HEAT REACTION IS Answer: heat stroke 117 93B Two milder forms of heat reactions are heat exhaustion and heat shock. Heat exhaustion, also known as heat fainting, is the mildest form of heat reaction. Moderate heat exposure may bring it on, especially in persons physically unfit. The victim feels tired, nauseated, possibly chilly, and their breathing will become fast and shallow. Also, they will have a weak, slow pulse and clammy skin. Recovery should be rapid when the victim is re- moved from the heat and rests with head lowered. Heat shock is a form of heat exhaustion which occurs in healthy people not acclimatized or used to working in hot climates. Because of inefficient sweating and inadequate fluid replacement, there is not enough fluid to supply circulation to all body organs. If the victim does not replenish lost salt, cramps, weakness, nausea, headache, fatigue, and dizziness will occur. The victim should be moved out of the heat, and fluid and salt losses re- placed. FIGURE 13B. IN HOT WORK SITES, COOL DRINKING WATER CONTAINING 0.1 PERCENT SALT SHOULD BE USED 118 938 FILL IN THE BLANKS OF THE TWO MILDER FORMS OF HEAT REACTION, HEAT EXHAUSTION USUALLY AFFECTS PEOPLE WHILE HEAT SHOCK AFFECTS PEOPLE, Answer: physically unfit, healthy 94B At the other extreme of the temperature scale is cold stress. As a whole, your body is less able to adjust to cold than to heat. Basically, you adjust to cold by walking or other kinds of exercising. Your body also attempts to keep you warm through two controls: the shrinking of blood ves- sels and shivering. When blood vessels near the surface of the skin shrink, the release of body heat through the skin is slowed down. However, this makes it difficult for blood to reach the hands and feet and causes an individual's hands and feet to become numb. A worker with cold, stiff, or numb hands will be less likely or able to perform manual tasks. Shivering generates body heat as a result of rapid muscle contraction, but again it will be difficult for any worker to do a skilled job while shivering. FILL IN THE BLANKS IN ADDITION TO VOLUNTARY EXERCISE, TWO BODY DEFENSES AGAINST EXTREME COLD CONDITIONS ARE AND THE OF BLOOD VESSELS. Answer: shivering, shrinkage 95B One of the two conditions that most frequently result from extended cold exposure is frostbite. Frostbite is local tissue damage, usually to the skin and muscles of either the hands or feet and in some cases both. Sometimes amputation is the only solution. If healing does occur, the affected 1imb may still be especially sensitive for years. 119 96B Another condition caused by long-term exposure to cold is hypothermia. Hypothermia occurs when your body loses heat faster than it can produce it. Often, wet clothing in combination with cool or cold temperatures produces hypothermia. The wet clothing pulls heat out of your body. Uncontrollable shaking, drowsiness, and apparent exhaustion are symptoms of hypothermia. If exposure continues until all energy resources are gone, the cold reaches the brain, creating a lack of good judgment on the part of the individual. However, the individual usually does not realize it and may deny any sickness. Without treatment, the internal temperature of the body falls leading to stupor, collapse, and death. Medical help should be obtained as soon as possible. FILL IN THE BLANKS TWO ILLNESSES RESULTING FROM COLD EXPOSURE ARE AND Answer: frostbite, hypothermia 978 Some other types of physical hazards are not as obvious as temperature extremes, but are nonetheless dangerous. For example, extremes in air pressure may have various side effects. People working under greater than normal pressure are targets for several problems. If the worker returns too quickly to normal air pressure, nitrogen in the body begins to form small bubbles in the blood and tissues of the body. Symptoms vary according to the location of the bubbles. Dizziness, paralysis, unconsciousness, cramps, and choking are all signs of different types of decompression sickness. To pre- vent this sickness, commonly called the bends, workers must return to normal pressure slowly. FILL IN THE BLANKS DECOMPRESSION SICKNESS, COMMONLY CALLED THE » RESULTS IN THE FORMATION OF BUBBLES IN THE BLOOD AND TISSUE OF THE BODY. Answer: bends, nitrogen 120 988 Under some working conditions at high pressure, carbon dioxide concentra- tions may be greatly increased, causing this gas to act as a narcotic, affecting a person's ability to think and make judgments. This condition can be minimized, but not prevented, by maintaining the oxygen concentration at a high level. A common complaint of those working in existing conditions that are under high pressure is pain and compression in the ears. Blockage of the eustachian tube which connects the middle ear and throat (which can happen when you have a cold or other sinus blockage) prevents the equalization of internal and external pressure. This may result in temporary or permanent hearing loss. FILL IN THE BLANKS AT HIGH PRESSURES, CARBON DIOXIDE MAY ACT AS A AND AFFECT A WORKER'S ABILITY TO AND MAKE . HOWEVER, PAIN AND COMPRESSION IN THE IS A COMMON COMPLAINT OF THOSE WORKING IN CON- DITIONS UNDER HIGH PRESSURE. Answer: narcotic, think, judgments; ear 99B Working under less than normal pressure (as is the case at high alti- tudes) also presents dangers. Oxygen starvation may occur in the thinner air. In areas where tests have shown oxygen concentration to be less than 19.5 percent ("normal" air contains 21 percent oxygen), you need to breathe an oxygen-enriched atmosphere, to prevent impaired senses and judgment. Oxygen starvation may also occur under conditions other than that of reduced pressure. It is not uncommon for workers in industry to experience deficiency of oxygen in the atmosphere of confined spaces. Therefore, you should check the oxygen content of any confined space before entering. FILL IN THE BLANKS WHEN WORKING UNDER LOW PRESSURE, WHERE OXYGEN CONCENTRATION IS LESS THAN 19.5 PERCENT, MAY OCCUR. TO AVOID IT, WORKERS MUST BREATHE AN ATMOSPHERE AND BE SURE TO CHECK BEFORE ENTERING. Answer: oxygen starvation; oxygen-enriched, confined areas 121 100B ITlumination and Radiation Sufficient, well-balanced Tighting is needed for safe working conditions. Good industrial illumination allows an individual to see comfortably and re- duces the chance of losses in visual performance. Poor illumination on the other hand can cause visual fatigue, eye strain and glare, and carelessness due to difficulty in seeing. Poor lighting also causes what is known as a delayed eye adaptation which occurs when you come from a brightly 1it envi- ronment to one that is dark. A familiar example is the visual change you experience when entering a tunnel while driving on a bright, sunny day. FILL IN THE BLANKS SAFE WORKING CONDITIONS EXIST IF THERE IS WELL-BALANCED THAT ALLOWS FOR COMFORT IN SEEING, REDUCING THE LOSS OF Answer: lighting, visual performance 101B Good illumination consists of two factors: quantity or amount of illum- ination, and quality which deals with the distribution of brightness. The amount or quantity of light which is considered to be desirable depends on the type of work that is being done. The highest illumination levels are recommended for tasks involving fine detail, Tow contrast, or prolonged work periods. The quality of illumination is concerned with the distribution of brightness in a work area. All elements of brightness have an effect on visibility and the ability to see easily, accurately, and quickly. As a result, fine detail work requires a higher quality illumination than others. In the mining industry, illumination with permissible lighting is required that is sufficient to provide safe working conditions. FILL IN THE BLANKS TWO FACTORS OF GOOD ILLUMINATION ARE AND » AND IN THE MINING INDUSTRY LIGHTING IS REQUIRED THAT PROVIDES WORKING CONDITIONS. Answer: quantity, quality, safe 122 1028 Up to this point, you have been given information concerning hazards that are able to be detected fairly easily by an individual. However, a hazard that cannot be readily sensed but that can cause serious effects to an individual's health and well-being is radiation. 7 7 \ M22 jit GON LS Si | He 4 : 1 7) 7 (TLLERRRE WEN RV NE 7 / N ANN) RNR ON WR Ww FIGURE 14B. RADIATION Radioactive materials are frequently present in industry as well as the medical profession. In the mining industry, concentrations of radioactive substances are generally higher in uranium mines than in other underground operations. Radiation in the coal mines of this country usually does not exist. Also, certain special equipment located in some mineral processing plants contain radioactive sources. These nuclear gauges are designed to generate radiation and are used in monitoring certain aspects of the indus- trial mining process. FILL IN THE BLANK A HAZARD THAT CAN HAVE A SERIOUS EFFECT ON AN INDIVIDUAL'S HEALTH AND WELL- BEING AND IS NOT EASILY DETECTED BY HUMAN SENSES IS CALLED . Answer: radiation 123 103B Airborne radiation in underground mining can always be traced to the same source, either uranium or thorium minerals. Traces of these two minerals can be found in almost any kind of soil and rock. Radon and thoron are radio- active gases released by minerals of uranium and thorium. Shortly after their release into the mine air, radon and thoron gases disintegrate. As a result of disintegration, new elements are formed. These new particles are known as radon and thoron daughters. A few seconds after formation, they become attached to the airborne dust in the mine air and can be inhaled by those who work in the area. Thus, airborne radiation is a mixture of these gases and their daughters. FILL IN THE BLANKS URANIUM AND THORIUM MINERALS CAUSE IN UNDER- GROUND MINES. Answer: airborne radiation 104B Radioactive materials emit energy in the form of one of five different types of ionizing radiation: alpha, beta, gamma, X-ray, or neutrons. When this energy is absorbed by cells and living tissues, it causes damage by a process called ionization. As a result of ionization, the radioactive par- ticles that pass through a cell interact with the atoms and molecuies which make up that cell and breaks them up. Some radioactive substances, however, only damage certain parts of the body due to how they were absorbed. No matter what the case, radioactivity can permanently destroy a cell or cause it to function improperly. What is frightening concerning ionizing radiation is the fact that when exposed, a person is not able to sense the radiation or the resulting damage to the body. FILL IN THE BLANK ALPHA, BETA, AND GAMMA RAYS ARE ALL TYPES OF RADIATION. Answer: ionizing 1058 The least amount of radiation is exhibited by alpha radiation, which can be stopped by a thin sheet of paper. At least a quarter of an inch of aluminum is required to stop the more penetrating ability possessed by beta 124 1058 particles. Like X-rays, gamma rays have a deep penetrating ability, and heavy shielding, such as several inches of lead, is required to halt their penetration. As you may know, X-ray technicians stand behind a thick lead shield while working in order to avoid exposure to radiation. This is be- cause of the penetrating ability of X-rays. The last form of radiation, neutrons, are so penetrating that they require special absorbent materials for shielding. CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING FORMS OF IONIZING RADIATION WOULD BE LEAST HARMFUL TO A HUMAN. A. ALPHA B. BETA C. GAMMA D. X-RAY E. NEUTRONS Answer: A 106B Alpha particles are hazardous only when taken internally (eaten or breathed in) because they are weakly penetrating. There are some beta par- ticles that are so weak that they also are only internal hazards. Stronger beta particles, gamma rays, X-rays, and neutrons are so penetrating that they are called external hazards. They are able to travel through space and pene- trate the body of the person standing nearby, damaging the ce'ls. However, both external and internal radioactive materials have the same damaging effects once inside the body. FILL IN THE BLANKS ALPHA PARTICLES ARE CONSIDERED HAZARDS AND PENETRATING RADIA- TION PARTICLES ARE CALLED HAZARDS. Answer: internal, external 125 107B Most of the radiation hazards that exist in the mines are internal haz- ards resulting from alpha radiation as is the case of inhaling radon and thoron daughters. However, uranium waste dumps can produce higher than usual concentrations of radioactivity and can emit gamma rays resulting in an external radiation hazard. TRUE OR FALSE IN THE MINING INDUSTRY, BOTH INTERNAL AND EXTERNAL RADIATION HAZARDS CAN EXIST. Answer: true 108B Because uranium miners are exposed to radioactive hazards, there seems to be a higher incidence of cancer and a decreased 1ife expectancy among these workers. When you consider contributors to Tung cancer such as radia- tion, combining it with cigarette smoking only creates a greater probability for cancer. Thus, people who smoke cigarettes on or off the job while being exposed to hazardous levels of radiation, are about 10 times more likely to get Tung cancer. Moreover, lung cancer related to radiation in mining shows up 6 or 7 years earlier among smokers. The following illustration would therefore be most appropriate for uranium miners. ( 2 > I] J FIGURE 15B. NO SMOKING 126 108B These workers also suffer, at young ages, medical changes usually associ- ated with aging. In addition, this radiation can also damage the genetic material of the cells which determines the inherited characteristics of your children. The rate of birth defects and prenatal deaths among children of workers exposed to radiation is twice the normal population rate. FILL IN THE BLANKS COMBINING RADIATION WITH CREATES A GREATER PROBABILITY FOR : Answer: cigarette smoking, lung cancer 1098 Another type of radiation, nonionizing radiation, consists of such things as radio waves, visible Tight, and the infrared or ultraviolet regions of the electromagnetic spectrum. The most common type of nonionizing radia- tion found in the mining industry is from ultraviolet (UV) radiation. If received in mild doses, this type of nonionizing radiation produces no imme- diate effect on a worker. However, UV radiation is absorbed by the first tissue it comes in con- tact with, the cornea of the eye. As a result, exposure to UV radiation for several hours will produce the sensation of sand in the eye. 110B The most common cause and source of exposure to UV radiation is from the sun. Individuals whose job requires them to work outside in the direct light of the sun may possibly receive an overexposure to UV radiation. This can cause a painful reddening of the skin (sunburn) and possibly blisters. In industry though, the most common source of UV radiation is from electric welding arcs. When considering any type of radiation, the best methods of preventing personal harm is separation from the source by distance or shielding. This will reduce the dose and limit the time of exposure. FILL IN THE BLANKS THE MOST COMMON TYPE OF NONIONIZING RADIATION IN INDUSTRY IS RADIATION WHICH AFFECTS A PERSON'S AND . HOWEVER, THE BEST WAY TO PREVENT HARM FROM RADIATION IS FROM THE SOURCE. Answer: ultraviolet, eyes, skin; separation 127 111B LET'S PAUSE AND REVIEW THE INFORMATION THAT HAS BEEN COVERED CONCERNING RECOGNITION OF PHYSICAL HAZARDS. 1. 10. 11. 12. 13: 14. IN INDUSTRY, EXPOSURE TO NOISE AND VIBRATION CAN LEAD TO IRRITATION AND LACK OF CONCENTRATION THAT CAN RESULT IN AN INCREASE IN FREQUENCY IS THE AND OF SOUND. THE MAJOR CAUSE OF HEARING PROBLEMS IS TRUE/FALSE - IMPACT AND IMPULSE NOISE ARE THE SAME. TRUE/FALSE - VIBRATIONS ARE NOT HARMFUL TO THE HUMAN BODY. TWO EXTERNAL FACTORS THAT AFFECT BODY CONTACT AND THE RATE AT WHICH THE BODY LOSES HEAT ARE AND THE THREE WAYS THE BODY LOSES HEAT IS THROUGH ’ ’ AND ‘ THE BODY GETS USED TO THE HEAT OF A NEW ENVIRONMENT THROUGH THE PROCESS OF ‘ TRUE/FALSE - IT IS MUCH EASIER FOR A PERSON TO ADJUST TO A COLD ENVIRON- MENT THAN TO ONE THAT IS HOT. A COMMON COMPLAINT OF THOSE WORKING UNDER HIGH PRESSURE IS PAIN AND COM- PRESSION IN THE WHILE THOSE WORKING IN LESS THAN NORMAL PRESSURE RUN THE RISK OF . POOR ILLUMINATION CAN CAUSE A. VISUAL FATIGUE B. EYE STRAIN AND GLARE C. DELAYED EYE ADAPTATION D E CARELESSNESS ALL THE ABOVE THE AMOUNT OF RADIOACTIVE SUBSTANCES IS GENERALLY FOUND TO BE HIGHER IN MINES THAN IN ANY OTHER UNDERGROUND OPERATIONS. AIRBORNE RADIATION IS ALWAYS THE RESULT OF EITHER OR MINERALS. WHEN A RADIOACTIVE SUBSTANCE PASSES THROUGH A CELL, IT INTERACTS WITH THE ATOMS AND MOLECULES WHICH MAKE UP THE CELL AND BREAK THEM UP BY A PROCESS CALLED ‘ 128 111B 15. THE MOST COMMON TYPE OF NONIONIZING RADIATION IN INDUSTRY IS Answers: 1. accidents 8. acclimatization 2. highness, lowness 9. false 3. overexposure 10. ears, oxygen starvation 4, false 11. 5. false 12. uranium 6. humidity, air movement 13. uranium, thorium 7. convection, radiation, 14. ionization evaporation 15. ultraviolet radiation If the correct answers to these questions were not clear, review before moving ahead. The final part of Section B deals with the recognition of both Biological and Ergonomic stress. 1128 Biological/Ergonomic Stress The final part of Section B will deal briefly with the recognition of biological and ergonomic stress factors. Biological stresses such as molds, fungi, bacteria, and viruses can produce many infections and diseases. This form of stress occurs most often in the health occupations or in occupations dealing with animals. However, it may be found in just about any job to some lesser degree. Examples of where biological stress could be found in the mining indus- try are in the contamination of potable water supplies or in unsanitary toilets, change rooms, and bathing facilities. Insects, rodents, and snakes can also be found in or around the mine. Interestingly, an example of bio- logical stress recently made national news. The outbreak of Legionnaires disease became a well publicized example in which the air conditioning system of several burl ings were contaminated by a certain bacteria. Death and i11- ness were the result. FILL IN THE BLANKS THE DANGER OF BIOLOGICAL STRESS IS THAT IT CAN PRODUCE MANY AND Answer: infections, diseases 129 113B In coal mines, according to 30 CFR 75.1712-3, all bathing facilities, change rooms, and sanitary toilet facilities shall be provided with adequate light, heat, and ventilation so as to maintain a comfortable air temperature and to minimize the accumulation of moisture and odors. Such facilities also shall be maintained in a clean and sanitary condition. Also, according to 30 CFR 75.1718, there shall be an adequate supply of potable water provided for drinking purposes in the active workings of a mine, and such water shall be carried, stored, and protected in sanitary con- tainers. TRUE OR FALSE REGULATIONS, IF PROPERLY FOLLOWED, WOULD TEND TO REDUCE BIOLOGICAL HAZARDS. Answer: true 114B Without proper testing equipment and laboratory procedures, sight, taste, and smell can be possible indicators, and in some cases be relied upon to provide an individual with the ability to recognize certain biological haz- ards. However, control of biological hazards must be considered on an indi- vidual basis. The seriousness of a biological hazard is determined by examining the nature of the hazard, the intensity of exposure, and the length of time a worker is exposed. COMPLETE THE FOLLOWING SENTENCE THE NATURE OF A HAZARD, ITS INTENSITY OF EXPOSURE, AS WELL AS THE LENGTH OF EXPOSURE DETERMINES . Answer: the seriousness of a biological hazard 115B This leads to our last category of industrial hazards that will be dis- cussed in Section B. Ergonomics deals with achieving the best possible balance, both physical and mental, between the worker and his job. In general, ergonomic stress does not directly produce injuries or diseases. Instead, by putting strain 130 1158 on the worker, they increase the chance of accidents. The dangers of such ergonomic stress as boredom, fatigue, and work pressure may not be as obvious, for example, as the dangers of harmful chemicals but they must also be pre- vented. FILL IN THE BLANKS ERGONOMICS CONCERNS THE BALANCE BETWEEN THE AND HIS Answer: worker, job 116B Ergonomics deals with the relationship of human and machine. Therefore, it is important to realize that routine tasks are generally performed more efficiently by a machine while an individual tends to perform better those tasks that call for responsibility and flexibility. TRUE OR FALSE DUE TO THEIR LOW ERROR RATE, ROUTINE TASKS ARE PERFORMED BEST BY EITHER KORKER OR MACHINE. Answer: false 117B One source of ergonomic stress is a badly designed work area. When looking at a work area and determining its effectiveness, one should consider space as well as the functional arm, leg, and body movements made by a worker while doing a job. The effectiveness of any such system that includes man and machine de- pends on integrating the body characteristics of the worker with the operat- ing equipment and work area. A badly designed work area not only distracts a worker, increasing the chance of accidents, but in some cases can endanger a worker's life. FILL IN THE BLANKS INTEGRATING BODY CHARACTERISTICS WITH THE OPERATION OF A MACHINE IS IMPORTANT IN THE PROPER DESIGN OF THE ‘ Answer: work area 131 1188 Proper body position is also important, especially in 1ifting and carry- ing. Unsafe acts are indirect causes of accidents. An example of such an indirect cause is improper 1ifting of materials. Proper procedures are im- portant to recognize. It is important to spend some time on the subject of handling materials because this type of accident accounts for more than one-fourth of all mine injuries. Every time a person handles materials, there is some risk involved. This is why back injuries are very common. However, back injuries usually are caused by lifting incorrectly rather than by lifting something that is too heavy. FILL IN THE BLANK BODY POSITION IS IMPORTANT IN LIFTING BECAUSE HANDLING OF MATERIALS ACCOUNTS FOR MORE THAN OF ALL MINE ACCIDENTS. Answer: one-fourth 1198 It is easier to 1ift a load when you are standing close to it. The same rule applies when you are handling materials in the mine. Bending over, how- ever, is not the way to get close to it. When you bend over, your spine (all the way from your shoulder to your lower back) takes most of the strain. Instead of bending over when you 1ift, bend your knees and straddle the load. This way is best because it assures that you will 1ift with your arm and leg muscles rather than with your back. Here are some basic procedures for 1ifting: 1. Keep your feet apart, one alongside and one behind the object. Do not reach out, but stand close to the Toad. 2. Keep your back straight (nearly vertical). Bend your knees, not your back. 3. Tuck your chin in. This helps keep your spine straight and firm. 4. Grip the object with your whole hand. Fingers have Tittle strength. Lift with your Teg and arm muscles instead of your back as much as possible. 5. Tuck your elbows and arms in near your body. Arms held away from the body lose strength. 132 1198 6. Keep your body weight directly over your feet. This provides more power and ensures a good balance. 7. When changing direction while carrying a load, turn your entire body including your feet and do not turn suddenly. 8. If the load is too heavy or interferes with your normal walking, get help. QD = cm Lo) «9 2 1 { tucked in k ¢ pin Back : $ One foot to the side AD fb straight WR (= One foot behind Elbows A tucked in Body weight directly over feet FIGURE 16B. LIFTING The most comfortable position in doing a job is usually the right one as well as being one that puts the least amount of stress on your body. TRUE OR FALSE WHEN HANDLING MATERIALS IN A MINE, BEND DIRECTLY OVER THE OBJECT AND LIFT USING THE MUSCLES OF YOUR ARM. 133 120B Equipment, therefore, must be designed so that it's comfortable and easy to operate. Monotony and repetitive motion are other ergonomic stresses that lead to boredom, carelessness, and accidents. In addition, when you are worried, it's harder to concentrate on your job and distractions lead to acci- dents. If you worry too much about how well you are doing your job, probably you will just do worse. LIST THREE ERGONOMIC STRESSES THAT LEAD TO CARELESSNESS AND ACCIDENTS. A. Answer: worry, monotony, repetitive motion, poor body position, and equipment design (Any three of these) 121B Fatigue is another problem common to all workers and it is represented by a decrease in an individual's ability to perform physically. As a result of fatigue, a tired condition exists and in many cases it is accompanied by soreness and pain. Fatigue, in fact, is the result of an accumulation of effects from vari- ous sources. Some of the factors that cause fatigue that should be recog- nized are: monotony; environmental factors such as light, climate, and noise; the intensity of both mental and physical work; psychological factors such as responsibility, worry, or conflict; and illness, pain, and eating habits. FILL IN THE BLANK A TIRED CONDITION THAT IS SOMETIMES ACCOMPANIED BY SORENESS AND PAIN CAUSING A DECREASE IN PHYSICAL PERFORMANCE IS Answer: fatigue 134 1228 Due to fatigue, an individual might experience increased irritability, depression, or a general weakness in drive and a dislike for work. With this in mind, it is interesting to note that maximum production takes place during the first hours of work when fatigue is lowest. As the shift continues, fatigue increases, production goes down, and the rate and chance of accidents increases. CIRCLE ONE OF THE CHOICES IN EACH SET OF PARENTHESES: AS TIME ON THE SHIFT INCREASES, PRODUCTION (INCREASES/DECREASES), FATIGUE ( INCREASES/DECREASES) , AND THE CHANCE FOR AN ACCIDENT (INCREASES/DECREASES). Answer: decreases, increases, increases 123B A11 of these industrial hazards--chemical, biological, physical, and ergonomic--threaten your health and safety. If not controlled, they can cause immediate injury or chronic illness. Other hazards (badly designed equipment, work pressure) threaten your safety, causing carelessness and increasing the rate of accidents. LIST THE FOUR CATEGORIES OF INDUSTRIAL HAZARDS. A. B. Answer: chemical, physical, biological, ergonomic 124B BEFORE MOVING AHEAD TO SECTION C, LET'S BRIEFLY REVIEW THE RECOGNITION OF BIOLOGICAL AND ERGONOMIC HEALTH HAZARDS. 1. THE SERIOUSNESS OF A BIOLOGICAL HAZARD IS DETERMINED BY A. EXAMINING THE HAZARD B. THE INTENSITY AND TIME OF EXPOSURE C. BOTH A AND B D. NONE OF THE ABOVE 135 1248 2. TRUE OR FALSE - ERGONOMIC STRESS PRODUCES MANY DISEASES. 3. TRUE OR FALSE - A BADLY DESIGNED WORK AREA INCREASES THE CHANCE OF ACCI- DENTS BUT IN NO WAY ENDANGERS LIFE. 4. TRUE OR FALSE - WHEN LIFTING YOU SHOULD KEEP YOUR FEET APART, KEEP YOUR BACK STRAIGHT, TUCK YOUR CHIN IN, GRIP THE OBJECT TIGHTLY WITH YOUR FIN- GERS, TUCK YOUR ELBOWS AND ARMS IN, AND DISTRIBUTE YOUR BODY WEIGHT DIRECTLY OVER YOUR FEET. 5. TRUE OR FALSE - FATIGUE CAN CAUSE A PERSON TO BE IRRITABLE, DEPRESSED, AND EVEN DISLIKE WORK. Answer: 1. C 2. False 3. False 4. False 5. True If the correct answers to these questions were not clear, review before moving ahead. If you are satisfied with your understanding of Section B and the recognition of health hazards, it is time now to move on to Section C - Control of Occupational Health Hazards. 136 INDUSTRIAL HYGIENE FOR THE MINING INDUSTRY SECTION C "EVALUATION AND CONTROL OF HEALTH HAZARDS" i Ei oT 8 —y LE ne n A = ks aa 1C This is Section C of the Industrial Hygiene Course entitled "Evaluation and Control of Health Hazards." The first two sections of this course dealt with a general understanding of what industrial hygiene is and how it is re- lated to the health and well-being of the worker. In this section, we will concentrate on the methods for evaluating and controlling health hazards thus minimizing your exposure to them. As was the case in the first two sections of this course, you will be asked questions throughout this section. Always answer the questions before checking the correct answer. The knowledge you obtain from this course will aid you in maintaining your health and well-being during your employment in a mining related occupation. Now go on to the next frame. 2C Evaluation and Measurement First, let's Took at the area of evaluation of health hazards. Evalua- tion is the process of making a decision concerning the degree or the amount of a health hazard that occurs as a result of an industrial operation such as mining. Evaluation is essentially a tool that is used for interpreting re- sults and for the purpose of conserving the health and well-being of the worker. CIRCLE THE CORRECT ANSWER USING AN INSTRUMENT TO DETERMINE THE AMOUNT OF OXYGEN IN THE AIR IS AN EXAM- PLE OF THE PROCESS OF A. RECOGNITION B. EVALUATION C. CONTROL D. NONE OF THE ABOVE 3 The extent of any health hazard depends on the nature of the hazard, the amount of exposure, and the length of exposure. In order to evaluate the ex- tent or presence of a health hazard, samples of the contaminant have to be 139 3C obtained. The sample location, the time the sample is taken, and the number of samples taken are all important factors in the evaluation process. Deter- mining the length of exposure is also important. This is required in order to determine the dosage of harmful substance that a person receives. FILL IN THE BLANKS THE TIME A SAMPLE IS TAKEN, ITS LOCATION, AND THE NUMBER OF SAMPLES ARE IM- PORTANT IN THE PROCESS, WHILE LENGTH OF EXPOSURE IS IMPORTANT IN DETERMINING THE A PERSON RECEIVES. Answer: evaluation, dosage 4c In order to take proper measurements, it is important to have a good knowledge about the working operation or process in which the measurements are to be taken. Also, the person taking the measurement should have a good knowledge about the contaminant in question. With this in mind, there should be enough measurements taken to establish what is known as the time weighted average. A time weighted average is an average exposure level determined by sampling at certain times during the period of a worker's exposure to a spe- cific contaminant that requires evaluating. These time weighted averages can then be compared to the TLV for the substance in question to determine the extent of the hazard. CIRCLE THE CORRECT ANSWER PROPER MEASUREMENTS ARE INFLUENCED BY A. KNOWLEDGE OF THE CONTAMINANT B. KNOWLEDGE OF THE WORK PROCESS C. ESTABLISHING TIME WEIGHTED AVERAGE D. ALL THE ABOVE 140 50 What is really being measured in such situations is the dosage that a worker receives. In order to accomplish this, certain sampling instruments can be attached directly to the worker and carried throughout the working day accomplishing the job of hazard evaluation. An example is illustrated in Figure 1C in which a dust sampler is attached to a worker to determine dust concentrations. FIGURE 1C. PERSONAL SAMPLER READY FOR USE COMPLETE THE FOLLOWING SENTENCE ONE OF THE BEST WAYS TO MEASURE THE DOSAGE OF A SUBSTANCE A WORKER RECEIVES THROUGHOUT THE WORK DAY IS TO Answer: attach a sampling device directly to the worker. 141 6C Another method of evaluation is to measure the concentration of a sub- stance in an individual's specific work area during selected intervals. After taking the measurements, the next step is to average the results and compare them to the length of exposure thus determining the time weighted average. An example of this method is shown in Figure 2C which shows the process of noise sampling in an underground mine. FIGURE 2C. NOISE SURVEY PROCEDURE COMPLETE THE FOLLOWING SENTENCE IN ADDITION TO AN ATTACHED PERSONAL SAMPLER, ANOTHER TECHNIQUE USED TO MEA- SURE DOSAGE IS TO Answer: take measurements in an individual's specific work area at selected in- tervals. 142 7 However, several factors could possibly affect the results of an evalua- tion. Examples of situations that will affect obtaining satisfactory mea- surements are such things as changing from day shift to night shift, changes in the seasons (winter to summer), changes in the work operation process, or the daily changes that seem to occur in the direction of air movement and temperature. These factors should be taken into consideration when evalua- ting the work environment. TRUE OR FALSE THERE IS A POSSIBILITY THAT THE ACCURACY OF DUST SAMPLES TAKEN DURING TWO DIFFERENT SHIFTS CAN BE AFFECTED. Answer: True 8C As was mentioned in Section A and B of this course, chemical hazards are the most numerous type found in the environment. These hazards can be further divided into two categories, the particulates (dust, smoke, mist, etc.), and gases or vapors. These categories also essentially determine how to measure for these particular type of contaminants. Measurements of gases and vapors using direct-reading instruments can be determined more readily than those in the particulate group because of the solubility of these substances. TRUE OR FALSE THE FACT THAT A SUBSTANCE IS A GAS OR PARTICULATE ALSO DETERMINES MEASUREMENT TECHNIQUES. Answer: True 9C Problems of skin contact also need to be measured. However, these con- taminants are much harder to evaluate than exposure to air contaminants. A wipe test might be one method of obtaining a sample for determining contami- nation levels. This technique is self explanatory and involves wiping the area of suspected contamination and then analyzing the results by laboratory tests. Another method might be laboratory analysis of a worker's clothing. In this situation though, studying the work habits of an individual might provide helpful information leading to the source of contamination. 143 9C FILL IN THE BLANKS THE WIPE TEST AND LABORATORY ANALYSIS ARE TECHNIQUES USED IN EVALUATING Answer: skin contamination 10C In addition to chemical hazards, there are also physical hazards such as heat and cold, radiation, pressure extremes, and noise that need to be evaluated. These hazards are usually measured by direct-reading instruments. Chemical or physical hazards that do not cause too serious a problem may just be sampled periodically. However, if certain chemical or physical agents have the potential to cause serious difficulty, continuous monitoring might be very desirable. FILL IN THE BLANKS MATERIALS THAT DO NOT CAUSE TOO SERIOUS A PROBLEM CAN BE MEASURED WHILE THOSE THAT CAUSE SERIOUS DIFFICULTY SHOULD BE MONITORED Answer: periodically, continuously 11C Direct-reading Instruments The direct-reading instruments used to measure or evaluate hazards can essentially be either electrical direct-reading instruments or color-change and stain-length instruments. The information that follows will help famil- iarize you with such equipment in case you come in contact with any of these instruments on the job. Those instruments that give a direct reading on a dial with the aid of an electrical meter of some sort are classified as electrical direct-reading instruments. An example of an instrument of this kind used in the mining in- dustry would be one that measures a combustible gas such as methane. Instru- ments of this type are depicted in Figures 3C(1) and 3C(2). 144 11 FIGURE 3C(1). HAND-HELD METHANE SPOTTER — FIGURE 3C(2). MACHINE-MOUNTED METHANE MONITOR 145 12C It is important to note, when taking a sample, that the indicator needle on some of these instruments rises sharply and then returns to the zero reading. This could indicate a very rich gas mixture so high that it cannot be read on the scale. However, if the person reading the scale did not see the needle rise and then return to zero, one might falsely assume the air to be safe. Also, these types of instruments have a tendency not to function properly in oxygen-deficient atmospheres. Remember when considering methane, its concentration must not exceed 1.0 volume percent in any working place when tested at a point not less than 12 inches from the roof, face, or rib. SE U. S. BUREAU OF MINES 377 373 H. 8S. PERMISSIBLE METHANOMETER™ ~~ | lem Helly FIGURE 3C(3). FIGURE 3C(4). HAND-HELD METHANE TESTER MINER TESTING FOR METHANE TRUE OR FALSE YOU CAN RELY ON ELECTRICAL DIRECT-READING INSTRUMENTS TO GIVE A CORRECT READ- ING IN ALL SITUATIONS AND UNDER ALL CONDITIONS. Answer: False 146 13C To monitor an oxygen-deficient atmosphere in a mine, a flame safety lamp is used. This lamp, pictured in Figure 4C(1), indicates the availability of oxygen in a certain area of a mine by the height of the flame. The flame de- creases in size in an oxygen-deficient atmosphere and goes out when the oxy- gen concentration drops below 16 percent. However, with methane present it will burn at 12 percent. FIGURE 4C(1). FLAME SAFETY LAMP 147 14C In order to assist the flame safety lamp in monitoring and measuring an oxygen-deficient atmosphere, an electrical direct-reading instrument called an oxygen indicator is available. Figure 4C(2) shows an example of such an instrument. It is capable of checking atmospheres for oxygen content in the range of 0 to 25 percent. PERMISSIBLE OXYGEN INDICATOR | PART NO MODEL 204 | Lh i FIGURE 4C(2). OXYGEN INDICATOR TRUE OR FALSE ELECTRICAL DIRECT-READING INSTRUMENTS AS WELL AS VISUAL INDICATORS ARE AVAIL- ABLE FOR DETECTING OXYGEN DEFICIENCY. Answer: True 150 To be sure a worker in a mine is getting enough ventilation and air to breathe, you have to be able to determine the amount of air reaching the worker. Such a measurement can be taken with an anemometer which measures wind force and speed. Figure 5C(1) pictures an anemometer and Figure 5C(2) shows the measurement procedure. 148 15C FIGURE 5C(1). ANEMOMETER FIGURE 5C(2). ANEMOMETER AIR MEASUREMENT FILL IN THE BLANK VENTILATION OR AIR FLOW IN A MINE IS MEASURED BY AN Answer: anemometer 149 16C Instruments that measure flammable gases do not always respond in the same way to different flammable gases. For example, if more than one flam- mable gas is present in the mine air, this can cause the reading on an in- strument to be wrong. This is particularly true following a mine fire or explosion when carbon monoxide and hydrogen, as well as lack of oxygen, all exist. For best results, these instruments have to be calibrated (adjusted) for the conditions under which they are to be used. If not, the meter reading may be meaningless. With this in mind, do not confuse calibration of the in- strument with following operating instructions; they are not the same. How- ever, operating instructions should also be read and followed for the best results. TRUE OR FALSE FOLLOWING A MINE FIRE WHICH PRODUCES MANY GASES, A CALIBRATED FLAMMABLE GAS DETECTOR CAN ALWAYS BE COUNTED ON TO GIVE ACCURATE MEASUREMENT RESULTS. Answer: False 17C Another potential hazardous condition that exists in the mining industry is respirable dust exposure. Even though the air in a mine is tested and found to be in compliance with the law pertaining to respirable dust, periodic dust monitoring is still required to insure dust levels stay within requirements. 18C One instrument designed for personal individual dust sampling is the gravimetric dust sampler pictured in Figure 6C(1). 150 18C FIGURE 6C(1). GRAVIMETRIC DUST SAMPLER This instrument consists of (a) a battery-powered pump, (b) a battery charger, and (c) a filter for personal monitoring which is designed to be worn. The pump draws the air through the cyclone where larger dust particles (larger than 10 microns) are removed. Then the smaller particles are trapped on a filter so they can then be weighed to determine the amount of respirable dust per cubic meter of air. 19C Figure 6C(2) shows another instrument (the MRE Gravimetric Respirable Dust Sampler) that gathers and collects area samples of dust on a filter. This filter is then sent to a laboratory for analysis to determine the level of respirable dust. 151 19C FIGURE 6C(2). MRE GRAVIMETRIC RESPIRABLE DUST SAMPLER TRUE OR FALSE ONCE A MINE HAS BEEN TESTED AND DETERMINED TO BE IN COMPLIANCE WITH THE LAW CONCERNING THE AMOUNT OF RESPIRABLE DUST, NO FUTURE MEASUREMENTS ARE REQUIRED WITH ANY DUST SAMPLING DEVICE. Answer: False 20C Noise is also a basic health hazard found in the mining industry. Noise mainly affects a person's hearing. However, it can also affect your ability to do a good job by interfering with on-the-job communication, increasing the chances that an accident will occur. Therefore, to help prevent excessive noise exposure, the Taw requires that noise sampling be conducted in coal mines. An electric direct-reading instrument used for the purpose of measuring sound levels is a sound level meter Tike the one pictured in Figure 7C. This instrument is designed to measure decibel (dBA) levels. 152 20C FIGURE 7C. SOUND LEVEL METER TRUE OR FALSE IT IS IMPORTANT TO KEEP DECIBEL LEVELS WITHIN PRESCRIBED LIMITS IN ORDER TO PROTECT HEARING AND PREVENT ACCIDENTS. Answer: True 21C The audio dosimeter, however, is used to measure total noise exposure during a working shift. It is worn by the miner and the percent of exposure is measured at the completion of the shift. FIGURE 8C. NOISE DOSIMETER 153 22C As we have discussed, many health and safety hazards can result from too much noise. Because of this, Federal regulations have been established which limit the time that you are permitted to be exposed to certain dBA levels in the mine. With this in mind, it is important to note the TLV's for noise. They indicate the decibel levels to which an individual can be exposed for a specific period of time. Exposure Time (Hours) dBA 8 90 6 92 4 95 3 97 2 100 1% 102 1 105 5 110 % or less 115 For example, if noise is recorded to be 110 dBA, then exposure to it must not exceed 30 minutes during an 8-hour shift. Once you have worked the number of hours listed at a specified dBA, you must not be exposed to 90 dBA or greater levels during the rest of the work shift. 230 Noise, however, has an interesting characteristic. If a machine causes a noise exposure of 90 dBA, another machine just like it operating beside it at the same time would only increase the noise exposure by 3 dBA. 154 23C FILL IN THE BLANKS IF NOISE IN A MINE IS RECORDED AT 105 dBA, THEN EXPOSURES IN THAT AREA DURING AN 8-HOUR PERIOD SHOULD BE LIMITED TO : Answer: 1 hour 24C Radiation, temperature, and pressure are other potential hazards that need to be evaluated in the mining industry to insure healthful conditions for the worker. Meters are used to measure alpha, beta, gamma, and X-radiation. Radioactive radon gas found in a mine is often measured by a battery- operated, portable pump like the one pictured in Figure 9C. (= eq CHG: @® Se. z 0) hs ie 7 FIGURE 9C. RADIOACTIVE RADON GAS BATTERY-OPERATED, PORTABLE PUMP 155 24C Also, film badges, similar to those small square devices you see attached to the chest pocket of an X-ray technician's lab coat, can be used to measure accumulated amounts or doses of radiation. These badges cannot be used to measure alpha radiation though because alpha particles will not penetrate the film paper used in the badges. FILL IN THE BLANKS TWO COMMON WAYS USED TO EVALUATE RADIATION HAZARDS ARE WITH AND Answer: meters, film badges 25C Various temperatures can affect how a person does a job, not to mention the amount of work produced. In the mining industry, however, a person is more likely to be exposed to high temperatures than Tow temperatures. Air temperature is measured with a thermometer usually referred to as a dry bulb thermometer. Humidity, or the moisture content of the air, is mea- sured with a psychrometer which gives a dry bulb (temperature) as well as wet bulb (humidity) readings. (See Figure 10C.) FIGURE 10C. SLING PSYCHROMETER 156 25C This instrument is slung around in a circular fashion in the air approx- imately 100 times while holding on to the handle until a stable reading is obtained. FILL IN THE BLANK HUMIDITY AS WELL AS AIR TEMPERATURE CAN BE MEASURED BY A Answer: psychrometer 26C Atmospheric pressure both high and Tow should be monitored. A barometer is the instrument used to measure atmospheric pressure. This instrument is referred to every evening on the television weather report. When working under high pressure, carbon dioxide in the atmosphere may increase enough to cause sleepiness. Congestion in the ears is also common at high pressures. Persons working at reduced pressure may experience oxygen starvation affecting their senses and individual judgment. Deficiency of oxygen from working in confined spaces is also common in industry. TRUE OR FALSE BECAUSE OF ITS MINOR EFFECT ON THE BODY, ATMOSPHERIC PRESSURE SHOULD NOT BE CONSIDERED IN EVALUATION OF POSSIBLE HEALTH HAZARDS. Answer: False 27C A11 the instruments mentioned and described so far except the film badges, psychrometer, anemometer, MRE dust sampler, gravimetric dust sampler, and the flame safety lamp are electrical direct-reading instruments. The accuracy of electrical direct-reading instruments can be affected by improper main- tenance, unreliable workmanship in the manufacturing process, poor calibration, interfering substances in the air, changes in the amount and flow of air, and weak or damaged batteries. The reliability of the measurements obtained are dependent on these factors. Therefore, frequent routine maintenance and calibration is required and necessary for such equipment to insure greater accuracy. 157 27C TRUE OR FALSE READINGS ON A METHANE SPOTTER CAN BE AFFECTED BY POOR CALIBRATION, IMPROPER MAINTENANCE, AND OTHER SUBSTANCES IN THE AIR. Answer: True 28C Up to this point we have basically examined electrical direct-reading instruments that give a direct reading on a meter of some kind. We have also mentioned other instruments that collect samples or give direct readings that are used along with the electrical direct-reading instruments. Other types of detection and identification instruments, color change and stain-length instruments, depend on a chemical reaction to give a reading. The reading or measurement is determined by comparing the color produced when the sample is taken with a standard color. The color and length of stain will tell you what substance has been sampled and how much of the substance is present. FILL IN THE BLANKS INSTRUMENTS THAT GIVE MEASUREMENT INDICATIONS BY COLOR CHANGE OR STAIN LENGTH DEPEND ON A TO PRODUCE THE READING. Answer: chemical reaction 29C Carbon monoxide is measured by instruments of this type. The most com- mon instrument used for this purpose is one that utilizes a detector tube with a chemical that changes color (from yellow to green) when exposed to carbon monoxide. The shade of green as a result of the test indicates the amount of carbon monoxide. This instrument is pictured in Figure 11C(1). 158 29C FIGURE 11C(1). CARBON MONOXIDE' TESTER The most common and accurate carbon monoxide detector indicates the length of stain produced by carbon monoxide drawn through a chemical sub- stance in a glass tube. (See Figure 11C(2)). FIGURE 11C(2). CARBON MONOXIDE LENGTH-OF-STAIN INSTRUMENT FILL IN THE BLANKS CARBON MONOXIDE CAN BE MEASURED BY BOTH AND INSTRUMENTS. Answer: color change, stain-length 159 30C Other length-of-stain indicators are also available for the detection of oxides of nitrogen, sulfur dioxide, and hydrogen sulfide. All are very simi- lar to the ones pictured in Figure 12C(1) and Figure 12C(2) which show a port- able length-of-stain hydrogen sulfide detector and nitrogen dioxide detector. FIGURE 12C(1). FIGURE 12C(2). PORTABLE LENGTH-OF-STAIN NITROGEN DIOXIDE DETECTOR HYDROGEN SULFIDE DETECTOR Each of these instruments is suitable for use at concentrations below, as well as above the TLV for a specific contaminant gas. However, the chemi- cals used in most of the detectors are sensitive and can react to more than one contaminant. This can cause confusion in correctly understanding test results. FILL IN THE BLANKS NITROGEN DIOXIDE CONCENTRATIONS BELOW THE TLV CAN BE MEASURED BY A - - INDICATOR. Answer: Tlength-of-stain 160 31C Various gases and vapors can also be detected by a single special instru- ment. The Scott Draeger Multi Gas Detector pictured in Figure 13C is not limited to measuring just one or two gases, but can be used to detect and measure more than 97 different gases and vapors by means of special detector tubes. FIGURE 13C. DRAEGER MULTI-GAS DETECTOR A harmful gas is indicated by a stain or color change of the chemicals in the tube. The color change that occurs, progressively increases in length as the concentration of the gas increases, indicating the result of the test without the need of a chart or graph. : TRUE OR FALSE DUE TO THE SMALL NUMBER OF DIFFERENT GASES THAT A MULTI-GAS DETECTOR CAN MEASURE, IT IS NOT USUALLY USED TO GIVE ACCURATE MEASUREMENTS IN SHORT PERIODS OF TIME. 161 32C Other multi-gas detectors are also available such as the one pictured in Figure 14C. FIGURE 14C. MULTI-GAS DETECTOR This particular instrument consists of a piston pump, various accessor- ies, filter, tubes, etc. It is capable of handling sampling that at one time required as many as 16 separate detectors. TRUE OR FALSE MULTI-GAS DETECTORS HAVE SIMPLIFIED THE SAMPLING PROCESS. Answer: True 33C A11 color change and length-of-stain instruments, however, do have some limitations. Differences in manufacturing processes and conditions cause variations in the tubes. Also, the accuracy of many of the tubes is affected by temperature extremes. 162 33C The biggest problem with these indicator tubes is interfering gases and vapors which cause poor test results. This places an added burden on the person who is interpreting the results. These tubes are also affected by the rate of air flow and also the amount of air drawn through the tube. Experi- ence, therefore, is an important factor in getting accurate results based on these variables. However, no matter what type of instrument is used, the final step in evaluating a hazard is deciding what the results of the samples obtained really say about a certain condition. CIRCLE THE CORRECT ANSWER THE MAJOR PROBLEM WITH INDICATOR TUBES IS A. MANUFACTURING CONDITIONS B. INTERFERING GASES AND VAPORS C. TEMPERATURE EXTREMES D. RATE OF AIR FLOW Answer: B 34C Let's pause and review what has been covered to this point in Section C concerning the evaluation and measurement of health hazards. 1. THE PROCESS OF MAKING A DECISION CONCERNING THE DEGREE OR AMOUNT OF A HAZARD IS TERMED 3 2. AN AVERAGE EXPOSURE LEVEL DETERMINED BY SAMPLING AT CERTAIN TIMES DURING A WORKER'S EXPOSURE TO A SUBSTANCE IS CALLED OBTAINING A 3. TRUE/FALSE - SAMPLING INSTRUMENTS ARE ATTACHED TO THE WORKER FOR THE PURPOSE OF PERIODIC EVALUATION DURING A PARTICULAR WORKING DAY. 4. TRUE/FALSE - INSTRUMENTS USED TO MEASURE CHEMICAL SUBSTANCES ARE SELECTED BASED ON WHETHER THE SUBSTANCE IS A PARTICULATE, GAS, OR VAPOR, WITH GASES AND VAPORS BEING THE EASIEST TO MEASURE. 5. PHYSICAL HAZARDS ARE MEASURED BY INSTRUMENTS. 163 34C 6. DIRECT-READING INSTRUMENTS USED FOR EVALUATION CAN BASICALLY BE EITHER DIRECT-READING INSTRUMENTS OR AND INSTRUMENTS. 7. COMBUSTIBLE GAS INDICATORS AND SOUND LEVEL METERS ARE EXAMPLES OF INSTRUMENTS. 8. TRUE/FALSE - DUE TO VARIOUS FACTORS AFFECTING THE ACCURACY OF ELECTRICAL DIRECT-READING INSTRUMENTS, FREQUENT MAINTENANCE AND CALIBRATION IS NECESSARY TO INSURE GREATER SUCCESS IN EVALUATION FINDINGS. 9. CARBON MONOXIDE, OXIDES OF NITROGEN, SULFUR DIOXIDE, AND HYDROGEN SULFIDE ARE GASES THAT ARE MEASURED BY OR INSTRUMENTS. 10. TRUE/FALSE - MULTI-GAS DETECTORS ARE DESIGNED JUST TO MEASURE ONE OR TWO SPECIFIC GASES. evaluation time weighted average False True direct-reading electrical, color change, stain-length electrical direct-reading True color change, length-of-stain False Answers: owopo~NoOTOP wn If the correct answers to the review questions were not clear, review before moving ahead. The next part of Section C will deal with the Control of Health Hazards. 164 35C Prevention and Control The evaluation process determines the effectiveness of controls that are used to reduce environmental stress to levels that you can put up with with- out damage to your health and well-being. The prevention and control of health hazards is everybody's responsi- bility. You must follow established rules and safety procedures. This means reporting and correcting dangerous situations right away. It also means wearing personal protective gear when required. Any accidental exposure of a worker to dangerous substances must be immediately reported. If the report is delayed, those exposed may suffer needlessly. Both management and employ- ‘ees must work together to obtain a truly healthful work environment. FILL IN THE BLANKS EVERYBODY HAS THE RESPONSIBILITY TO AND HEALTH HAZARDS. Answer: prevent, control 36C The best way to protect workers from hazards is to act before anyone is hurt. Several methods may be used to control hazards. Substitution of a less dangerous agent can eliminate or reduce a hazard. Dangerous operations can be isolated by being enclosed or they can be removed to special areas. Wet methods keep dust from polluting the air. Many atmospheric pollutants can be removed by local exhaust ventilation or diluted by general ventilation. Good housekeeping keeps wastes and dusts under control. Also, personal pro- tective equipment should be used when the environment can't be made completely safe. The following is a complete list indicating the various methods for controlling environmental stress factors: ® Substitution of a Tess harmful material for one which is dangerous to your health. e Change or alteration of a process to minimize worker contact. e Isolation or enclosure of a process or work operation in order to reduce the number of persons exposed. eo Employment of wet methods to reduce generation of dust in operations such as mining and quarrying. 165 36C ® Local exhaust ventilation at the point of generation or dispersion of contaminants. ® Minimizing the exposure time to maintain worker exposure at a safe level through administrative controls. eo General or dilution ventilation with clean air to provide a safe atmosphere. eo Personal protective devices, such as special clothing, ear, eye, and respiratory protection. ® Good housekeeping, including cleanliness of the workplace, waste dis- posal, adequate washing, toilet, and eating facilities, healthful drinking water, and control of insects and rodents. ® Medical controls. e Training and education. TRUE OR FALSE IN ORDER TO BEST PROTECT A WORKER FROM A HAZARD, CORRECTIVE ACTION SHOULD BE TAKEN ONLY AFTER A PERSON HAS BEEN HURT. Answer: False 37C It is important to look at each of these methods of control in more detail. First let's look at substitution. It just makes sense to replace a toxic material with a harmless one, that is, substituting a less harmful substance for one that is dangerous to your health. This serves to help eliminate industrial health hazards. For example, the solvent trichloroethylene could be used in place of carbon tetrachloride. In addition, less dangerous situations can also be substituted. An example of this would be evaluating welds without radiation. Substitution is indeed one of the most effective ways to decrease danger. 166 37C FILL IN THE BLANKS ONE OF THE MOST EFFECTIVE WAYS OF DECREASING INDUSTRIAL HAZARDS IS Answer: substitution 38C Worker contact can be minimized by changing certain work processes for other less dangerous ones. To reduce ergonomic stress, easily operated and comfortable equipment can be substituted for outdated, awkward equipment. Also, if the cleaning of contaminated clothing or equipment can be done by machines instead of by hand washing, the health and safety hazard decreases. An ideal chance to improve working conditions is often presented when there is a change in process. Of course, most of these changes are made to improve the quality or to reduce the cost of production; only occasionally are changes made to improve the environment in the plant. However, we nust never lose sight of this possible benefit. TRUE OR FALSE A CHANGE OR MODIFICATION OF A PROCESS TO ELIMINATE A HEALTH HAZARD IS ALWAYS A GUARANTEE OF IMPROVING INDUSTRIAL HYGIENE CONDITIONS. Answer: False 39C Exposure problems can sometimes be solved by isolating some potentially dangerous operations from the workers nearby. Isolation can take many forms. It may be by a physical barrier (an acoustic box, for example) to contain the noise from a whining blower or a screaming rip saw. Isolation can also be accomplished by time, such as providing semi-automatic equipment so that a worker does not have to constantly remain near the noisy machine. Finally, distance and remote controls can provide isolation. Since an enclosure will prevent or minimize the escape of harmful sub- stances into the workroom atmosphere, enclosing the process or equipment is a desirable method of isolation and control. After considering substitution for some of the more highly harmful substances or situations, enclosure should be one of the first measures attempted. 167 39¢ FILL IN THE BLANKS THREE ALTERNATIVES BY WHICH INDIVIDUALS MAY BE ISOLATED FROM POTENTIALLY DAN- GEROUS OPERATIONS ARE ’ » AND . SEVERE HAZARDS PRESENTED BY DUST OR FUMES ARE FREQUENTLY BEST SOLVED BY : Answer: physical barriers, time, distance; complete enclosure 40C Wetting dust often keeps it from polluting the air. The application of water or other suitable Tiquid at the source of dust can often minimize or greatly reduce dust hazards. This method is frequently used for silica, coal, and loose dusts. Wetting down is one of the simplest methods of controlling dust. Figure 15C illustrates the wetting method. FIGURE 15C. USING WATER FOR WETTING DUST 168 40C The proper wetting of the dust, however, determines its effectiveness. The addition of a wetting agent to the water may be required. Also, proper disposal of the wetted dust is needed before it dries out and is redispersed. Water under high pressure is used successfully during mining of the ore face. By forcing water through the drill bits used in rock drilling operations, tremendous reductions in dust concentrations have been achieved. FILL IN THE BLANKS IN ORDER THAT WETTING DUST IS EFFECTIVE AS A METHOD OF CONTROL, ADDITION OF A AND PROPER OF WETTED DUST MIGHT BE REQUIRED. Answer: wetting agent, disposal 41C Limited operations which require relatively few workers or where control by any other method is too difficult or too expensive may benefit by ventila- tion. These workers could be protected from dust, for example, by local exhaust ventilation. This involves removing the dust at its source. Vacuum systems with funnel-type inlets suck in dust or other atmospheric contaminants where they are created. Mists, fumes, gases, vapors, and dusts can be controlled this way. The purpose of a local exhaust system is to trap the air contami- nant near to its source so as to protect the worker from exposure to harmful concentrations. FIGURE 16C. LOCAL EXHAUST VENTILATION 169 41C FILL IN THE BLANKS A METHOD OF DUST CONTROL IN WHICH VACUUM SYSTEMS SUCK CONTAMINANTS AWAY FROM SMALL WORK AREAS THROUGH VENTS IS Answer: local exhaust ventilation 42C Local exhaust vents are effective in keeping down the amount of air pollutants. This technique may be especially useful at grinding wheels, where mineral dust presents a danger. This is also true with spray painting, when inhalation of the chemical mist may cause illness. Local exhausts are most effective when the source of the contaminant is in a small, limited area. For example, in a laboratory chemicals are often stored under a hood, and an ex- haust fan runs whenever the chemicals are in use. FILL IN THE BLANKS LOCAL EXHAUST IS MOST EFFECTIVE WHEN THE SOURCE OF THE CONTAMINANT IS IN A Answer: limited area 43C When the source of the air pollutant covers too large an area, local ex- haust is not practical. General or dilution ventilation may then be used. In this system, fresh air (which may be temperature- and humidity-controlled) is fed in large amounts into the work area. The polluted air is then drawn out through exit vents, windows, or doors. There must be enough space and air movement so that the pollutant is diluted before it reaches the workers. The purpose of a general or dilution ventilation system is to distribute fresh air at a comfortable temperature and humidity throughout a working area. Since it relies on fresh air to merely dilute harmful substances, a general ventilation system is not usually the most effective method of controlling hazards. 170 43C FILL IN THE BLANKS WHEN THE SOURCE OF THE CONTAMINANT IS SPREAD OVER A LARGE AREA, VENTILATION IS OFTEN USED. FOR THIS METHOD TO WORK, THERE MUST BE ENOUGH SPACE SO THAT THE POLLUTANT IS BEFORE IT REACHES THE WORKER. Answer: general; diluted a4 There are several principles of good practice for general ventilation systems: e Fresh air coming into the work area should circulate through worker- inhabited areas (such as the working face of a coal mine) where there are harmful substances, in order that the workers be able to breathe air that is as uncontaminated as possible. eo Cross drafts should be avoided by distributing air evenly throughout the work area (such as using brattice curtains in coal mining). eo The inlet of the general ventilation system should be located well away from the exhaust system outlet and other sources of contaminated air. e Air should be treated--that is, heated, cooled, humidified, or de- humidified--so as to maintain a comfortable and healthful atmosphere for the workers (such as in deep metal/nonmetal underground mines). 45C Occasionally it may be possible to reduce a worker's exposure to hazards by Timiting the amount of time spent in the hazardous area. The reduction of the amount of time actually engaged in work activity can be an effective con- trol of hazardous work conditions. This is a type of administrative control. By Timiting the exposure time, it is possible to maintain the total exposure to less than what is allowed by the threshold 1imit values. For example, limiting the amount of exposure time to noise levels in excess of 90 dBA may serve to keep the daily exposure below the allowable limit. Rest periods are also useful in reducing effects of exposure to hazard- ous conditions. For example, conditions of high temperature and humidity have adverse effects on the human body and can produce heat stress problems. 171 45C Rest periods allow the body time to recover from these stressful conditions. Administrative controls should only be used in conjunction with other control procedures mentioned in this section. FILL IN THE BLANK CONTROLS USED TO REDUCE THE AMOUNT OF EXPOSURE TO HAZARDOUS CONDITIONS BY LIMITING THE EXPOSURE TIME ARE CALLED CONTROLS. Answer: administrative 46C In addition to changing the environment to eliminate or reduce hazards, dangerous situations can be reduced by good housekeeping. If dust on the floor and shelves is vacuumed away regularly, it won't move into the atmos- phere and be inhaled or have a chance to irritate the skin. Cleaning equip- ment reduces breakdowns and malfunctions which may physically hurt you or cause financial damage to the company. Spills, splatters, and overflows when not cleaned up right away can lead to slips and falls. Hazardous wastes and trash must not be allowed to pile up and create a hazard. In addition, all materials used and produced should be stored properly for the same reason. Also, insects and rodents carry disease and should be controlled. FILL IN THE BLANKS CLEANING UP SPILLS AND SPLATTERS, VACUUMING DUST IN THE WORK AREA, TAKING CARE OF WASTES AND TRASH, AND STORING ALL MATERIALS USED AND PRODUCED ARE EXAMPLES OF . Answer: good housekeeping 47C Personal hygiene habits are also important. With this in mind, adequate washing, toilet, and eating facilities as well as sanitary drinking water should be provided. In addition, if your clothes or body get dirty, or if you work with chemicals, you should shower and change clothes before leaving work. Contaminated work clothes and clean street clothes should be kept in separate lockers. These precautions assure that your skin will not be exposed to irritating contaminants after work. To protect others (like your family), contaminated clothing should not be taken home. Good housekeeping is an im- portant part of an occupational health program. It is another tool that is used for preventing the spread of dangerous contaminants. 172 47C TRUE OR FALSE CORRECT PERSONAL HYGIENE HABITS PROTECT YOU, AS WELL AS OTHERS WHO ASSOCIATE WITH YOU. Answer: True 48C Personal protective equipment gives further protection when the environ- ment cannot be made totally safe. Its biggest drawback is that it doesn't eliminate or reduce the hazard. Its failure means immediate exposure to danger. In some cases, the protective device may stop functioning without your realizing it. There are different protective devices for each job and for many dif- ferent parts of the body. All applicable safety devices should be worn on the job at all times. However, personal protective equipment should be em- ployed only as a secondary alternative, after the other controls which we have mentioned have been ruled out. FILL IN THE BLANKS THE BIGGEST DISADVANTAGE OF PERSONAL PROTECTIVE EQUIPMENT IS THAT IT DOES NOT OR THE HAZARD. Answer: eliminate, reduce 49C Personal protective equipment includes such things as gloves, aprons, boots, overalls, goggles, hard hats, ear protectors, and respirators. What equipment is worn depends on the hazards of each particular job. The eyes need goggles or safety glasses for protection from flying ob- jects, massive blows, and chemical burns. Special goggles are designed to keep out chemical splashes and atmospheric pollutants that filter out ultra- violet and infrared light. Face shields are used to protect the face from harmful substances and foreign objects. There are numerous eye and face protection devices available. 173 49C Figure 17C pictures some of the face and eye shields available for use. FIGURE 17C. EYE AND FACE SHIELDS The most important point to remember, however, is that if these eye and face shields are not comfortable, they will not be worn, even when they are needed or required. FILL IN THE BLANK ALTHOUGH THERE ARE MANY EYE AND FACE SHIELDS AVAILABLE, _ 15. THE KEY TO WHETHER OR NOT THEY ARE WORN. Answer: comfort 174 50C Ideally, noise should be reduced or controlled at the source of its pro- duction. However, this is not always possible. Therefore, various controls may be required to conserve hearing. Examples of personal protective equip- ment for the cars are large earmuffs, sound shields, or ear plugs Tike those pictured in Figure 18C. "8 FIGURE 18C. EAR PROTECTION 51C Muffs offer the best personal protection against loud noise. Fitting them for a person is not a problem and they can easily be adjusted. Some workers, however, say muffs are uncomfortable and many types cannot be worn with safety hats or welding shields. Ear plugs, on the other hand, are more comfortable if fitted properly. However, they do not offer as much protection and are only recommended for use in an area of moderate noise levels. Drawbacks to their use, according to many workers, is that initially they have to be fitted by a medical ex- pert and then properly inserted each day by the employee for the best effec- tiveness and comfort. Also, aside from the fact ear protectors can be uncomfortable, many workers do not feel they need protection because hearing loss is gradual and goes unnoticed. They also need to be cleaned daily to prevent ear infections. 175 51C FILL IN THE BLANKS THE TYPE OF PERSONAL PROTECTIVE EQUIPMENT THAT OFFERS THE BEST RESULT AGAINST LOUD NOISE IS THE » WHEREAS ARE USED FOR PROTEC- TION AGAINST MODERATE NOISE. Answer: muffs, plugs 52C Environmental controls are more effective than protective clothing or protective creams and they do not depend on the worker for success. However, in situations where there is prolonged or repeated contact with dermatitis- producing solvents, chemicals, or dust, protective clothing should be worn to control the hazards. Such clothing includes gloves, aprons, boots, coveralls, and other items. The proper protective article should be selected for the specific situation. As an example, some types of rubber will withstand the solvent trichloroethylene, but will become spongy and disintegrate when ex- posed to a lacquer solvent. Selection of the proper protective article is important. If the harmful, irritating substance is in dry form, cotton gloves and clothing that can be laundered easily will do the job. If the irritating substance is liquid, clothing that the liquid cannot penetrate should be chosen. Again, these articles should be laundered frequently. 530 Reflective, aluminized clothing can be used for intermittent protection against radiant heat. Special care must be given to such garments so as to preserve the shiny surface which is the essential part of protection for you. High heat loads can be made bearable by use of air-cooled jackets and suits while protection against ionizing radiation is available in the form of lead- bearing materials. Also, hard hats need to be worn in most industries. A hard hat protects your head against massive blows from swinging equipment, falling objects, and numerous other hazards. Steel-toed boots that prevent feet from being crushed are also a necessity in most industries. 176 53 FILL IN THE BLANK THE SUCCESS OF PROTECTIVE CLOTHING DEPENDS ON THE USING THEM AND HOW THEY ARE USED. Answer: worker 54C Protective creams, although their effectiveness varies, help reduce skin contact simply from the necessity of having to wash them off. When this occurs, the contaminant on the skin is washed away. These creams protect against such things as dust, water soluble materials, oil, and solvents. They should be used when other protective equipment is not suited for a particular climate, in situations where manual dexterity is required and bulky clothing hinders the work process, and where certain clothing creates a safety hazard near moving machinery. FILL IN THE BLANK ALTHOUGH PROTECTIVE CREAMS PROTECT AGAINST DUST, WATER SOLUBLE MATERIALS, OIL, AND SOLVENTS, THEIR REAL ACCOMPLISHMENT IN DOING THE JOB OF CONTROL COMES WHEN THEY ARE FROM THE SKIN ALONG WITH THE CONTAMINANT. Answer: washed 550 One of the major hazards found in a coal mine is coal dust. There may also be other dusts, such as silica and other rock dusts. In addition, mists from paint sprays and other toxic dusts, mists, and fumes may be en- countered. In those cases where dusts, gases, and other pollutants in the air can- not be controlled, gas masks or respirators may be necessary. When you in- hale through a gas mask, the air is drawn through chemicals contained in the canister, and they remove harmful gases from the air. Gas masks should be used if the eyes must be protected or if high concentrations of gases or vapors are probable. Since gas masks supply no oxygen, there must be suffi- cient oxygen in the atmosphere. 177 FILL IN THE BLANKS 55C IF DUST AND OTHER AIR POLLUTANTS CANNOT BE CONTROLLED, THE USE OF OR CAN PROVIDE PROTECTION. FOR A GAS MASK TO BE EFFECTIVE, THERE MUST BE IN THE AIR. Answer: gas masks, respirators; sufficient oxygen 56C A respirator is a device which fits over the mouth and nose and prevents dust from being inhaled into the throat and Tungs. There are two basic types of respirators used in the mines: the supplied-air and the filter-type. Supplied-air respirators are devices which provide the wearer with an independent supply of clean air. This air may be supplied through a small air line (hose) from an air compressor or from compressed air cylinders. If you have to wear a supplied-air respirator, you will receive special training on how to use it. Figure 19C illustrates a supplied-air respirator. FIGURE 19C. SUPPLIED-AIR TYPE RESPIRATOR TRUE OR FALSE SUPPLIED-AIR RESPIRATORS ARE USED MAINLY WHEN THERE IS A LOT OF DUST IN THE WORK AREA. Answer: false 178 57C The filter-type, or air-purifying, respirator is the type most commonly used in the mine. These respirators use a filtering system which cleans the air before it is inhaled so that the wearer breathes clean, non-contaminated air. An example would be an air-purifying respirator such as a gas mask. There are two kinds of filter-type respirators. One is a chemical cart- ridge type, which is designed to remove only certain dangerous gases and vapors. An example of this type is your self-rescuer, which protects you from carbon monoxide. The other is the particulate filter type, which removes dust, mist, fumes, and sprays from the air. The type of respirator used depends on the type of contaminant in the area. Figure 20C illustrates the various filter-type respirators. Reusable Particulate Cartridge Disposable Particulate Type Type Type FIGURE 20C. FILTER-TYPE RESPIRATORS CIRCLE THE CORRECT ANSWER IF YOUR JOB IS DRILLING, THE TYPE OF RESPIRATOR YOU SHOULD WEAR IS A. SUPPLIED-AIR B. PARTICULATE FILTER C. SELF-RESCUER D. CHEMICAL CARTRIUGE TYPE RESPIRATOR 179 58C The particulate filter type respirators work much like the air filter on a car, furnace, or air conditioner. Air can pass through a filter, but other things cannot. The filter catches the other things and prevents them from passing through. When you wear a respirator, you breathe the contaminated air into the respirator fil- ter. Here a porous material traps the contaminant but allows air to pass through and the clean air to enter your lungs. CLEAN AIR IN LUNGS FIGURE 21C. HOW A RESPIRATOR WORKS 180 58C CIRCLE THE CORRECT ANSWER THE PARTICULATE RESPIRATOR REMOVES DUST FROM THE AIR BY A. A CHEMICAL REACTION B. PROVIDING OXYGEN C. FILTERING OUT CONTAMINANTS D. BOTH A AND C 590 The effectiveness of a particulate respirator is limited by the amount of dust in the air and the type of work you are doing. A filter can only hold so much dust before it becomes clogged. So if you are in a very dusty area or if you are breathing hard, you will pull more dust into the filter and clog it faster than if there is little dust or you are breathing easily. The effectiveness of this respirator also depends on the tightness of the seal between the facepiece and your face. If it does not seal tightly, dusty air can leak in. Poor face seals can be caused by beards, long side- burns, chewing or talking, and missing dentures. Since you must remove the respirator to spit, you should not chew tobacco while wearing one. CIRCLE THE CORRECT ANSWER BECAUSE THE EFFECTIVENESS OF A RESPIRATOR DEPENDS ON THE TIGHTNESS OF THE SEAL BETWEEN THE FACEPIECE AND YOUR FACE, YOU SHOULD BE AWARE OF POOR FACE SEALS THAT CAN BE CAUSED BY A. UNUSUAL FACIAL FEATURES B. BEARDS AND LONG SIDEBURNS C. DIRTY FILTERS D. NOT BITING DOWN ON THE MOUTHPIECE Answer: A and B 181 60C A limitation of any respirator, however, is that it hinders communica- tion. Communication is difficult because the respirator interferes with the sound of your voice. Communicating can break the face seal, so you should talk as Tittle as possible. Because respirators as well as gas masks make talking difficult, a system of hand and head movements should be arranged for communication, since commu- nication with others is a vital safety precaution. Whether using breathing aids or not, telling others where you are going and how long you will be gone is a good safety habit. If you get into trouble and cannot signal for help, someone will begin to check for you when you do not return on time. Also, equipment operators will know where to expect you if they must work or travel near you. FILL IN THE BLANK THE FACT THAT RESPIRATORS MAKE TALKING DIFFICULT INDICATES A NEED FOR AN ALTERNATE METHOD OF AS A VITAL SAFETY PRECAUTION. Answer: communication 61C The most important limitation, however, is that the particulate respira- tor should be used only to protect you against dusts, mists, and sprays. It does not protect you against carbon monoxide, methane, or other harmful gases often found in the mine. Also, it is not a substitute for a supplied-air respirator or self-contained breathing apparatus and must not be used for protection while fighting fires. 62C Some people do not like to wear respirators. They say that they make it hard to breathe, that they are warm and uncomfortable, or that they make eye glasses hard to wear. It is important to remember that a respirator protects you. Anything on your face may feel warm and uncomfortable, but you can min- imize the discomfort by adjusting the mask properly. Forcing the air through a filter when you breathe may make it more difficult to breathe. However, after a few minutes it should no longer be noticeable. If you wear glasses, you need to get a respirator that fits properly with your glasses on. Re- member, change the filter when it becomes clogged. This will help make it easier to breathe through the respirator. If used and maintained properly, respirators can and do protect your health. 182 62C TRUE OR FALSE IN WORK ENVIRONMENTS WHERE HARMFUL GAS IS FOUND, PARTICULATE RESPIRATORS CAN BE SUBSTITUTED FOR A SUPPLIED-AIR RESPIRATOR. Answer: False 63C The proper type of respiratory protective equipment should be selected according to the following procedures: 1, Identify the substance or substances against which protection is required. Know the hazards of each substance and its significant characteris- tics. Determine the levels of air contamination, oxygen deficiency, and the conditions of exposure. Determine if there are any personal capabilities and characteristics essential to the safe use of the required devices or procedures. Determine what facilities are needed for maintenance of the respira- tor. CIRCLE THE CORRECT ANSWER SELECTION OF THE PROPER TYPE OF RESPIRATORY PROTECTIVE EQUIPMENT IS BASED ON WHICH OF THE FOLLOWING: A. B. THE TYPE OF SUBSTANCE AGAINST WHICH PROTECTION IS REQUIRED. THE LEVELS OF AIR CONTAMINATION, OXYGEN DEFICIENCY, AND CONDITIONS OF EXPOSURE. THE HAZARDS AND SIGNIFICANT PROPERTIES OF THE SUBSTANCE AGAINST WHICH PROTECTION IS REQUIRED. ALL OF THE ABOVE. NONE OF THE ABOVE 183 64C An effective medical program can also help control and prevent certain health hazards. These medical programs essentially serve as a check on es- tablished controls by helping to identify control failures that must be corrected. Routine physical exams after an initial preemployment physical will check employees exposed to harmful materials for possible disease signs. TRUE OR FALSE EFFECTIVE MEDICAL CONTROL PROGRAMS WILL ONLY HELP PREVENT CASES OF OCCUPA- TIONAL DISEASE. Answer: True 65C However, a main method of control and your main protection against these assorted hazards is just knowing about them. Through education and training you can recognize, report, and avoid them. To gain the most benefit, you must constantly be receptive to new information as it develops, and be able to apply the information you have learned. Although this course outlines some general precautions and controls, specific instructions and considera- tions are needed for each situation. You must understand why safety measures need to be taken and what will happen if they are not. FILL IN THE BLANKS YOUR MOST IMPORTANT DEFENSE AGAINST INDUSTRIAL HAZARDS IS AND Answer: education, training 66C Application of Controls A11 of these methods of hazard prevention and control apply to different situations. Some examples can be used to examine how all or several of the previously mentioned preventive measures can be applied. For example, flam- mable 1iquid hazards, Tike those with solvents, can be controlled in various ways. These hazards are often overlooked, perhaps because the use of flam- mable liquids is so common. The dangerous situation arises when the liquid evaporates into the air and forms an explosive vapor. Nearby sources of ig- nition such as open flames, hot surfaces, and sparks from the operation of electrical equipment or discharges of static electricity may be enough to ignite the air-vapor mixture. 184 66C One technique used to eliminate this hazard is the substitution of a less dangerous liquid for the flammable one. Proper storage, handling, and dis- pensing limit the danger when flammable or explosive substances must be used. Reducing the amount of the liquid will also reduce the hazard because less vapor will form. Vapors can also be controlled by being enclosed, removed by local exhaust ventilation, or diluted by general ventilation. Special waste containers for soaked solid waste should be available and emptied frequently. Liquids, too, must be properly disposed of, not just poured down the drain. Figure 22C pictures a portable safety can used for the storage of flammable liquids. Spring action cover over spout. Flame Arrester Screen Pressure Flammable liquid FIGURE 22C. PORTABLE SAFETY CAN CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING CAN BE PROPER METHODS OF CONTROLLING FLAMMABLE LIQUIDS? SUBSTITUTION ENCLOSURE VENTILATION PROPER STORAGE, HANDLING, AND DISPOSAL ALL THE ABOVE m OO oo © > 185 67C When it comes to dermatitis, the best method of control is to avoid skin contact. This is hard to do, however, the places you work should be designed to assure minimal contact. Another good dermatitis control measure is for you the employee to become educated and informed about any harmful material that is required to be used. Personal protective equipment such as gloves, boots, and shoes should be used as a secondary defense against dermatitis. Also, this personal protec- tive equipment must be in good repair and clean to be effective. Protective creams, although they provide only limited protection against dermatitis, benefit the worker mainly from having to wash the cream off. COMPLETE THE FOLLOWING SENTENCE THE PRIMARY DEFENSE AGAINST DERMATITIS IS Answer: to avoid skin contact 68C In the mining industry, epoxy resin is used frequently in roof bolting. These epoxy resins can be a mild to strong skin irritant depending on the person exposed. However, some of the most severe exposures comes from direct contact with the hardener. To prevent dermatitis from epoxy resins, the following control measures can be helpful: eo Select hardeners that have the least irritating effect. e Use just as much hardener as necessary. ® Provide adequate local exhaust ventilation. e Minimize handling. ® Separate the work area. eo Educate the worker about the hazard. eo Use specific personal protective equipment. eo Insist on good personal cleanliness. e Avoid touching face or other skin with anything that is contaminated. eo Use good housekeeping. 186 68C FILL IN THE BLANK SOME OF THE MOST SEVERE DERMATITIS REACTIONS WITH EPOXY RESIN COMES FROM CON- TACT WITH THE Answer: hardener 69C Gases, dust, mist, and fumes also need to be controlled. Dust, mist, and fumes should, when possible, be controlled at their source of production. When this type of control is not possible, then other desired control methods such as the following are needed to limit exposure: ® Enclosure e Isolation ® Substitution of less hazardous material o Keep materials moist ® Local exhaust ventilation ® General ventilation eo Perform work when fewer people are around, reducing the number of workers exposed ® Reduce working time eo Use respiratory protective equipment TRUE OR FALSE GASES, DUST, MIST, AND FUMES ARE BEST CONTROLLED BY SUBSTITUTION. Answer: False 187 70C Noise can also present a hazard, and as such needs to be controlled. Every noise problem consists of a source of sound and a path along which it travels as well as a receiver for the sound. Controlling noise at the source is a design problem. Noise control along the path of sound is accomplished by shielding, enclosure, or distance. However, noise control methods include: e isolation ® machine insulation e absorption material on the walls e substitution of less noisy equipment e reduction of exposure time e personal protection equipment TRUE OR FALSE NOISE CAN BE CONTROLLED AT ITS SOURCE, PATH, AND THE PLACE OF RECEPTION. Answer: True 71C Because a worker in the mines is more likely to suffer heat stress than cold stress, control of excessive heat is important. Heat can be controlled by shielding hot equipment, increasing air movement and the supply of fresh air, acclimatization of the worker, isolation of the source of heat if pos- sible, and through the use of protective clothing. Of all these control methods, personal acclimatization is perhaps the most important. Acclimati- zation allows a person to do a hot job with Tess physical stress than a per- son who is not used to hot conditions. FILL IN THE BLANK OF ALL THE CONTROL METHODS FOR HEAT, IS PERHAPS THE MOST EFFECTIVE MEANS OF CONTROL FOR THE WORKER. Answer: acclimatization 188 72C Radiation is another hazard for which multiple precautions are needed. Especially since many of the effects are still unknown, great care must be taken to avoid any unnecessary exposure. Radioactive wastes must never be left unprotected. Systems using radioactive material must be properly main- tained and isolated. All nearby workers must be shielded with the right kind and thickness of material. If the source of the radiation is a dust or gas, ventilation is needed to keep the work area safe. The ventilation system must be able to hold the radioactive waste until it can be disposed of in the right way. 73C The levels of radioactivity must be continually monitored to make sure they stay within the safe limits. In fact, the shorter the time of exposure, the smaller the radiation dose received. Also, the more shielding placed between radioactive material and a person the less radiation a person will receive. Distance between a person and a radiation source is also a key pro- tection tool. In addition, radiation meters can be worn to monitor each worker's accumulated exposure to certain types of radiation. These precau- tions are the employer's responsibility, but if any advisable precautions are not taken, it's up to the worker to report the problem. Everyone's safety depends on it. FILL IN THE BLANKS PROTECTION FROM LARGE DOSES OF RADIATION ARE PROVIDED BY ’ » AND ‘ Answer: time, distance, shielding 74C Many ergonomic stresses can also be prevented or lessened. Some ergo- nomic stresses, such as worry, are difficult to eliminate but must still be taken into account. In addition it must be realized that ergonomic stresses will affect production and accident rates. To reduce the ergonomic stress of fatigue, several things can be done. Your worktime and breaks should be arranged so they create the least fatigue. Each worker must be suited to his task, taught the best way to do the job, and above all follow work instructions. 189 74C The stress of monotony and boredom can be alleviated by arranging a periodical job switch. Also, back injuries, a common accident occurring in the industrial setting, can usually be avoided by 1ifting and carrying the right way. When lifting, keep your feet apart with one foot beside the ob- ject and one behind it. Keep your back straight up and down, and tuck in your arms. Grip the whole object, and 1ift it, keeping your weight directly over your feet. FIGURE 23C. CORRECT LIFTING Other injuries to the musculo-skeletal system caused by ergonomic stresses can be avoided if you use well-designed equipment and do not work in uncomfortable positions for extended time periods. TRUE OR FALSE SOME ERGONOMIC STRESSES (LIKE WORRY) ARE DIFFICULT TO ELIMINATE SO YOU MIGHT AS WELL FORGET ABOUT THEM. Answer: False 190 75C Carcinogens are those substances that can be absorbed, swallowed, or in- haled that cause cancer. Because they exist in industry, workers must have some form of protection if they are exposed to an occupational carcinogen for any length of time. These carcinogens must be restricted to areas where ex- posure can be prevented and these areas should be identified by signs and warning labels. Also, because of the type of hazard, eating, drinking, storing food, and smoking should be banned in these areas. Individuals that work around known cancer-causing substances should: eo Use required personal protective equipment. eo Wash and shower if required. e Properly handle contaminated clothing and equipment. e And be able to take emergency steps in case of accidental exposure. FILL IN THE BLANKS BECAUSE CARCINOGENS CAN BE SWALLOWED, ABSORBED, OR INHALED, INDIVIDUALS SHOULD NOT , > » OR STORE IN AREAS WHERE CANCER-CAUSING SUBSTANCES EXIST. Answer: eat, drink, smoke, food 76C Accidents and injuries happen even when all possible safety precautions are taken. Because of this, even if you are following safety rules and pro- cedures, as well as good personal cleanliness habits, you must pay attention to any warnings your body might give you. Be sure to report any dangerous conditions to your supervisor. Accidental exposures to unsafe substances should be reported immediately. If you follow these guidelines, the chances of injury and illness are greatly reduced. FILL IN THE BLANKS YOUR MOST IMPORTANT DEFENSE AGAINST INDUSTRIAL HAZARDS IS AND . Answer: education, training 191 77C LET'S PAUSE AND REVIEW THE FINAL PART OF SECTION C WHICH DEALS WITH THE CON- TROL OF HEALTH HAZARDS. PUT THE LETTER OF THE PROTECTIVE EQUIPMENT IN FRONT OF THE HAZARD IT PROTECTS YOU FROM (MORE THAN ONE LETTER MAY GO ON ONE LINE): i. 2. 3. 4. 10. 11, HANDLING CHEMICALS A. GAMMA AND X-RAYS B. HEAT 6. WORKING WITH SOLVENTS D. HEARING LOSS E. JECTS, AND CHEMICAL BURNS F. MASSIVE BLOWS, FLYING OB- TO THE EYES BLOWS TO THE HEAD FROM SWINGING EQUIPMENT AND H. FALLING OBJECTS RESPIRABLE DUST OR GASES ERGONOMIC STRESS GOGGLES OR SAFETY GLASSES AIR-COOLED SUIT REFLECTIVE SUIT EARMUFFS OR PLUGS SUITS MADE OF LEAD-BEARING MATERIAL GLOVES BARRIER CREAMS STEEL-TOED BOOTS HARD HATS RESPIRATOR OR GAS MASK AVOID SKIN CONTACT ACCLIMATIZATION WELL-DESIGNED EQUIPMENT TRUE OR FALSE - THE PREVENTION AND CONTROL OF HEALTH HAZARDS IS THE WORKERS" RESPONSIBILITY. ONE OF THE MOST EFFECTIVE WAYS OF DECREASING AN INDUSTRIAL HEALTH HAZARD IS BY A. CHANGING THE PROCESS B. ISOLATION C. SUBSTITUTION D. VENTILATION E. WETTING DOWN THE SUBSTANCE 192 71C 12. THE REDUCTION OF TIME SPENT IN A HAZARDOUS AREA IS AN EFFECTIVE CONTROL MEASURE AND IS ACCOMPLISHED THROUGH ; 13. ONE OF THE SIMPLEST METHODS OF CONTROLLING DUST IS BY 14. THE TYPE OF VENTILATION THAT REMOVES A CONTAMINANT AT ITS SOURCE IS WHILE VENTILATION MERELY DILUTES THE AIR. 15. WHEN THE ENVIRONMENT CANNOT BE MADE SAFE USING OTHER CONTROLS, CAN GIVE PROTECTION. Answers: 1. f, g, k 2. @ 3. b,c, 1 4, ¥, @,% 5, d 6. a 7. h, i 8. J 9. m 10. false 11. substitution 12. administrative controls 13. wetting down 14. local exhaust, general 15. personal protective equipment If the correct answers to the review questions were not clear, review the last part of Section C before moving ahead. The final section of this course deals with the specific relationship of industrial hygiene to the mining industry. 193 . FP 0 har A BE " bs si A 2% Ps TRE 1% ha Soph. EEL by ns © on ok yl "an z Tu atk Faighh, 5 - oh af “mu - oo el % i . iE NS i, oo INDUSTRIAL HYGIENE FOR THE MINING INDUSTRY SECTION D "INDUSTRIAL HYGIENE AND MINING" ¥ = CE ¥ * 3 Vaal X pt 1 fo 2 1D This is Section D, the final section in the Industrial Hygiene Programmed Instruction Course. The first three sections of the course provide a founda- tion of information concerning industrial hygiene. Also, various examples were used in the first three sections relating industrial hygiene to the mining industry. The final section of the course, however, will focus specif- ically on accidents and industrial hygiene health hazards found in the mining industry. Again, follow the same procedures in completing the final section of the course as you did in the first three sections. 2D Accidents Accidents resulting in death or lost work time have typically been higher among young, new workers. In fact, accidents are the leading cause of death in the United States among young workers between 15 and 44 years of age. Figure 1D indicates the percentage of deaths caused by accidents in these age groups. Accidents 31% Heart Disease Cancer 13% 13% All Other Causes 43% FIGURE 1D. ACCIDENT RATES 197 3D Accidents usually result from one or more unsafe acts or unsafe condi- tions, or both. Because of this relationship, unsafe acts and conditions are identified as the indirect causes or symptoms. In turn, indirect causes are usually traceable to poor management policies and decisions, or to personal or environmental factors which are identified as basic causes. FILL IN THE BLANK ACCORDING TO STATISTICS, PERSONS 15 TO 44 ARE MOST LIKELY TO DIE FROM Answer: accidents 4p While most accidents are complex, many of them can be prevented by elim- inating one or more of the causes. A successful accident prevention program, however, requires the complete support and cooperation of all employees — from top management to the individual worker. Although mining has been considered to be one of the most hazardous of all industries in the United States, improvements have been made in recent years through research, improved equipment and mining techniques, inspections, and education and training. In fact, accident rates have decreased markedly in areas where miners are trained to recognize and control hazardous condi- tions, and are able to take steps needed to protect each other. TRUE OR FALSE A SUCCESSFUL ACCIDENT PREVENTION PROGRAM IS DETERMINED BY THE INDIVIDUAL WORKER. Answer: false 5D The fact that mining is a hazardous occupation is proven by the statis- tics which show that in 1984, 188 miners lost their lives. These figures include those from coal, metal, nonmetal, stone, as well as sand and gravel mines. The following table shows the number of deaths that occurred in differ- ent types of mines. 198 5D Coal Metal Nonmetal Underground - 96 Underground - 15 Underground - 2 Surface - 15 Surface - 4 Surface -3 Prep Plant - 7 Mills - 3 Mills -3 Stone Sand/Gravel Underground - 2 Surface - 11 Surface - 14 Mills - 13 As you can see, the majority of the fatalities happened in the under- ground areas of the mines. Not shown was the fact that falls of the roof, face, or rib, handling material, ignitions, transportation and haulage, and improper use or malfunction of machinery were the main causes of both injury and death. 6D As a result of accidents and deaths, laws have been passed to enforce safe practices in the mines. Federal responsibilities and duties pertaining to protection of the health and safety of America's miners currently are be- ing carried out under provisions of the Federal Mine Safety and Health Act of 1977. Also, improved technology, special procedures, and protective de- vices have been developed to protect each miner. Regulations outline these procedures and make their use mandatory. These, along with education and training, will do much to decrease the accident and death rates associated with mining. FILL IN THE BLANKS STATISTICS PROVE THAT MINING IS A OCCUPATION AND AS A RESULT HAVE BEEN PASSED TO ENFORCE SAFE AND HEALTHFUL PRACTICES. Answer: hazardous, laws 7D The Law Prior to 1977, miners' working conditions were governed by two separate laws: the Federal Coal Mine Health and Safety Act of 1969, and the Federal Metal and Nonmetallic Mine Safety Act of 1966. The problem with this situa- tion was that the miners were not receiving training on health hazards. The 1977 Act also required the National Institute of Occupational Safety and Health (NIOSH) to conduct research and establish limits for contaminants in the workplace. 199 8D Mine Hazards There are many potential safety and health hazards in underground and surface mines. Precautions are taken and safety programs enacted, but their effectiveness depends on individual safety consciousness and a good industrial hygiene program. Everything you will learn concerning health and safety in the mines will be useless unless you practice and utilize what you learn. FILL IN THE BLANKS HEALTH AND SAFETY EFFECTIVENESS IS DEPENDENT UPON AND A GOOD PROGRAM. Answer: safety consciousness, industrial hygiene 9D Why then do unsafe acts happen? Safety rules may not be enforced, or perhaps they are not known to the miners. Often, rules are simply ignored. Some miners may be unwilling to accept new safety measures because they think they know best how to do their jobs. Also, some miners think they are immune to accidents. Perhaps a miner has gotten by with unsafe acts before and as a result thinks nothing will happen to him. It may also be "easier" not to follow the rules. It is very important, especially in the mining industry, that everyone follows all safety rules and procedures. Personal factors (for example, recklessness, excitability, and ignorance of safe practices) are often the causes of accidents and injury. In any case, not following safety rules only leads to more accidents; it does not increase efficiency. Most accident pre- vention methods are just common sense and apply to everyone. FILL IN THE BLANKS RECKLESSNESS, EXCITABILITY, AND CARELESSNESS ARE EXAMPLES OF WHICH OFTEN CAUSE ACCIDENTS. Answer: personal factors 200 10D Your industrial hygiene program should focus on your specific situation as a miner--underground or surface mining--and the industrial hygiene prob- lems associated with the job. In addition to the human factor, general mine hazards include mine gases, dust, radiation, noise and vibration, poor illumination, and physical exertion and stress in a range of temperatures and humidities. Many of the hazards are associated with the underground mine at- mosphere (for example, explosions, asphyxiations, lung diseases). Let's now take a Took at each of these hazards as they occur in underground and surface mining operations. FILL IN THE BLANKS ALTHOUGH MANY OF THE HAZARDS IN THE MINING INDUSTRY ARE ASSOCIATED WITH UNDERGROUND MINE ATMOSPHERE, YOUR INDUSTRIAL HYGIENE PROGRAM SHOULD FOCUS ON YOUR . Answer: specific situation 11D Mine Atmosphere and Gases First, let's discuss the mine atmosphere and the gases that make up the atmosphere since many potential hazards (explosions, asphyxiation, lung disease) result from mine dust and gases. Air is the common mixture of gases found in operating mines. It supplies the oxygen needed by those who go underground. In addition, it removes unde- sirable gases and dust produced during mining. Also, in deep mines it may be used to remove heat and cool the miners. As air passes through a mine, it picks up other gases as well as the dust formed during mining. At the same time, air loses oxygen to the sur- roundings and to the men in the mine (that is, oxygen is absorbed by coal, the other rocks and timbers, and is also consumed by men). In addition, during the winter months, most mines tend to dry out. The reverse process occurs in the summer, so that mines during this season of the year become damp. 201 11D CIRCLE THE CORRECT ANSWER THE MOST COMMON GAS FOUND IN AN OPERATING MINE IS: A. AIR B. OXIDES OF NITROGEN C. CARBON DIOXIDE D. METHANE 12D The amount of oxygen consumed by people working in a mine depends in part on the rate at which they work. As an individual's exercise rate increases and becomes more vigorous the more oxygen the individual will consume. However, the composition of mine air also depends on the rate at which air flows through the mine. Under normal conditions, the flow rate is specified in such a manner that the contaminant gases do not render the air unsafe for human use. FILL IN THE BLANKS THE AMOUNT OF OXYGEN IN A MINE IS DETERMINED BY INDIVIDUAL AND THE MINE . Answer: consumption, airflow 13D The current standards for coal mines (30 CFR 75.301) prescribe that: all active workings shall be ventilated by a current of air containing not less than 19.5 volume per centum of oxygen, not more than 0.5 volume per centum of carbon dioxide, and no harmful quantities of other noxious or poisonous gases; and the volume and velocity of the current of air shall be sufficient to dilute, render harmless, and to carry away, flammable, explosive, noxious, and harmful gases, and dust, and smoke and explosive fumes. The minimum quantity of air reaching the last open crosscut in any 202 13D pair or set of developing entries and the last open crosscut in any pair or set of rooms shall be 9,000 cubic feet a minute . . . . The minimum quantity of air in any coal mine reaching each working face shall be 3,000 cubic feet a minute. Further 30 CFR 75.301-2 states that: Concentrations of noxious or poisonous gases, other than carbon dioxide, shall not exceed the current threshold Timit values (TLV) as specified and applied by the American Con- ference of Governmental Industrial Hygienists. 14D Similarly, for metal and nonmetallic mines 30 CFR 57.5-1 states: . the exposure to airborne contaminants shall not exceed, on the basis of a time weighted average, the threshold 1imit values adopted by the American Conference of Governmental Industrial Hygienists, as set forth and explained in the 1973 edition of the Conference's publication. . . . 15D Surface mines present an interesting situation concerning air contamina- tion. Although there is less likelihood of dangerous levels of gases becoming trapped in aboveground mines, it is possible. Poor air circulation in a pit with heavy haulage traffic and excavating machinery might create a hazard. A miner working in and around running equipment, especially in enclosed areas where engines are running, may be exposed to carbon monoxide gases. 16D Contaminant gases are often produced in mines under both normal and ab- normal conditions. For example, fires, diesel engines, blasting operations, and in some cases, the coal and the adjacent strata also liberate harmful gas. Diesel engines, fires, and explosives may produce carbon monoxide as well as oxides of nitrogen. Other gases (methane, hydrogen sulfide, excess nitrogen, hydrogen) are also found in some mines. TRUE OR FALSE MINING CONDITIONS MAKE IT POSSIBLE FOR A WORKER TO BE EXPOSED TO VARIOUS CON- TAMINANT GASES. Answer: true. 203 17D Taking all this into consideration, oxygen is the gas that is most important to you because it is needed to support life. It is colorless, odor- less, and tasteless, and slightly heavier than air. Air usually contains 21 percent oxygen, although we can function satis- factorily with lesser or greater amounts. However, when oxygen content drops below 16 percent most people will have some breathing difficulty. At oxygen levels below about 10 percent many people become unconscious. In a methane- free atmosphere containing about 16 percent oxygen, a flame safety lamp is extinguished, and as you know you never enter an area when a flame safety lamp is extinguished. FIGURE 2D. FLAME SAFETY LAMP FILL IN THE BLANKS THE GAS THAT IS MOST IMPORTANT IS , HOWEVER, WHEN THE LEVEL OF THIS GAS GOES BELOW PERCENT, PERSONS WILL EXPERIENCE Answer: oxygen, 16, breathing difficulty 204 18D Oxygen concentrations above those found in the atmosphere, and air at abnormal pressures, may produce safety and health hazards that can affect the body adversely. For this reason, special care must be taken when working in tunnels under such conditions because of the presence of higher than normal oxygen pressure. 19D Nitrogen is also found in the atmosphere and in some rocks. This color- less, odorless, tasteless gas normally makes up 78 percent of the air we breathe. However, it is slightly lighter than air, and is the main dilutant of oxygen in the air. Nitrogen becomes dangerous only when it takes up such a large part of the atmosphere that oxygen is driven out. This creates an oxygen deficiency that causes buzzing in the ears, rapid heartbeat, and a dizzy feeling. FIGURE 3D. AN OXYGEN-DEFICIENT ATMOSPHERE WITH AN EXCESSIVE AMOUNT OF NITROGEN WILL NOT SUSTAIN LIFE FILL IN THE BLANKS THE MAIN DILUTANT OF OXYGEN IN THE ATMOSPHERE IS WHICH IN SUFFICIENT AMOUNTS CAN CAUSE . Answer: nitrogen, oxygen deficiency 205 20D In addition to nitrogen and oxygen, other gases make up the remaining 1 percent of the normal atmosphere. Although these gases are found in small concentrations compared to oxygen and nitrogen, they can be dangerous when their TLV's are exceeded. One of these gases is carbon dioxide. It is found in the soil, in coal, and in many rocks and is formed by living animals, fires, and explosions. Carbon dioxide is colorless with a slight acid taste when present in the air in high concentrations. 21D Carbon dioxide, however, has several peculiar properties of interest to the miner. First, it is heavier than air and so it tends to flow into Tow- lying areas. Next, because of its role in the respiration process, the body can tolerate only small quantities in the surrounding air. For example, we find that even one-half of 1 percent carbon dioxide affects our breathing. Miners exposed to this concentration breathe a little deeper and faster, that is, their lung ventilation increases. When 3 percent carbon dioxide is pres- ent in the air, lung ventilation doubles. A 10 percent carbon dioxide level can be tolerated for only a few minutes, because at this point the lungs cannot accept and exchange any more oxygen. (See Figure 4D below.) a Oo Oo T on Oo o »N oO Oo LUNG VENTILATION, > oO I | | L o 2 4 & 8 Zo CO, IN AIR FIGURE 4D. THE SUPPLY OF OXYGEN THROUGH THE LUNGS INCREASES WITH AN INCREASE IN THE CARBON DIOXIDE (C02) CONCENTRATION 206 21D CIRCLE THE CORRECT ANSWER HIGH CONCENTRATIONS OF CARBON DIOXIDE TEND TO A. PRODUCE ACID IN THE ATMOSPHERE B. INCREASE LUNG VENTILATION C. CAUSE EXPLOSIONS D. GATHER AT THE ROOF OF A MINE Answer: B 22D Another gas, carbon monoxide, is colorless, odorless, and tasteless, but it is slightly lighter than air. By law, carbon monoxide is never to exceed .005 percent (50 ppm) of a mine atmosphere. This gas is produced by fires and heated combustibles. A miner working around running equipment, especially in enclosed areas, may be exposed to carbon monoxide poisoning. Since carbon monoxide has no locally irritating effects, an individual may never realize the danger that is present. FILL IN THE BLANKS HEALTH HAZARDS CREATED BY OFTEN GO UNNOTICED BECAUSE THIS GAS HAS NO LOCALLY IRRITATING EFFECTS. Answer: carbon monoxide 23D Carbon monoxide poses a health problem because it combines more readily than oxygen with the hemoglobin of the blood. Once the hemoglobin combines with carbon monoxide, it cannot combine with oxygen, therefore the oxygen- carrying capacity of the blood is limited. For example, a concentration of 500 ppm of carbon monoxide in the air is enough to kill a person in a matter of just 3 hours. (See Figure 5D1.) This concentration would block about 50 percent of the hemoglobin in the blood. (See Figure 5D2.) 207 23D 200 No Perceptible Effects o l 2 3 EXPOSURE TIME , HOUR CARBON MONOXIDE CONCENTRATION, PPM FIGURE 5D(1). EFFECTS OF CARBON MONOXIDE CONCENTRATIONS AND EXPOSURE TIME ON HUMANS BR 2 60 E Possible Death S 5 g 40 L Come ® Dizziness, Possible Collapse S _ ] : Throbbing Headache s 20 | 1 3 Possible Headache 2 Le L. ¢ | ss 0 le C8 lS] ad | 200 400 600 800 CARBON MONOXIDE CONCENTRATION IN AIR, PPM FIGURE 5D(2). LONG-TERM EFFECTS OF CARBON MONOXIDE IN COMBINATION WITH THE HEMOGLOBIN OF THE BLOOD The rate that carbon monoxide combines with blood depends on exposure time, the concentration of the gas, and the activity of the individual who is exposed. (The more strenuous the activity the faster the blood saturation.) 208 24D Carbon monoxide in large amounts is also flammable. Such amounts of carbon monoxide may be formed following a fire or explosion. However, the greatest danger to a miner is from breathing carbon monoxide. Properly main- tained equipment and good ventilation will reduce the risk associated with the gas because this gas can be a killer in poorly ventilated areas. FILL IN THE BLANKS THE BIGGEST CARBON MONOXIDE THREAT TO A MINER COMES FROM THE GAS IN AREAS. Answer: breathing, poorly ventilated 25D Methane is another gas found in mines. It is the most common flammable gas found in coal and in rocks that contain combustible materials. Methane is an odorless, colorless, tasteless, highly flammable gas which when re- leased tends to rise to the roof area of a mine because it is lighter than air. Methane also acts like nitrogen and reduces the oxygen concentration by dilution when mixed with air. This characteristic causes methane to act as an asphyxiant. It is estimated that in the past 60 years over 10,000 deaths have occurred in the nation's coal mines as a result of the presence of this gas. Most of these deaths were due primarily to the fact that when methane concen- trations reached 5 to 15 percent in the air, flammable explosive mixtures were produced. Once ignited, the flames tend to produce toxic products such as carbon monoxide, oxygen-deficient atmospheres, and in many cases go on to ignite dust, timber, coal, and other combustibles. FILL IN THE BLANKS TWO HAZARDS THAT CAN RESULT FROM EXCESSIVE AMOUNTS OF METHANE ARE AND y Answer: explosions, asphyxiation 209 26D Methane therefore is not permitted to accumulate in mines. The regula- tion found in 30 CFR 75.309 states: If, when tested, a split of air returning from any working section contains 1.0 volume per centum or more of methane, changes or adjustments shall be made at once in the ventilation in the mine so that such returning air shall contain less than 1.0 volume per centum of methane. 27D Another flammable gas is hydrogen. It is lighter than air and as a re- sult tends to rise to the roof area of a mine. However, this gas is not normally found in mine air unless a fire or explosion has occurred, although small quantities may be found near battery charging stations. Hydrogen is colorless, odorless, tasteless, and forms flammable mixtures with air when the atmosphere contains at least 4 percent of hydrogen. FILL IN THE BLANK A FLAMMABLE GAS THAT IS NOT NORMALLY FOUND IN MINE AIR EXCEPT AROUND BATTERY CHARGING STATIONS IS . oS Answer: hydrogen 28D Oxides of nitrogen can also create a hazard. They are formed at high temperatures by diesel and gasoline engines, electrical discharges, and blasting operations. Most of these gases are harmful because they form cor- rosive acids when mixed with the moisture in the lungs. The TLV's of these gases are listed as 25 ppm for nitric oxide and 5 ppm for nitrogen dioxide. These gases are readily detectable and usually cause no difficulty as long as proper precautions are available to dilute them with fresh air as they are formed. FILL IN THE BLANKS DIESEL AND GASOLINE ENGINES AS WELL AS BLASTING OPERATIONS IN THE MINES TEND TO FORM OXIDES OF AT HIGH TEMPERATURES, HOWEVER, THEY WILL USUALLY CAUSE NO DIFFICULTY IF THEY ARE WITH FRESH AIR. Answer: nitrogen, diluted 210 29D Nitrogen dioxide is the main oxide of interest. This gas is almost colorless in low concentrations and becomes reddish-brown at higher concen- trations. Nitrogen dioxide is heavier than air, has the odor of blasting fumes, and is quite irritating. It causes throat and lung irritation when inhaled in even small concentrations. 30D Sulfur dioxide is a colorless, suffocating, irritating gas with an easily recognized, bad, sulfurous smell. This gas is also much heavier than air. It is formed in fires that involve iron pyrites and occurs when blast- ing for certain sulfide ores. It has a rather Tow threshold limit value (5-parts-per-million of air) but, because it is an extreme irritant, it is very easy to detect. For this reason a person is not apt to remain for any length of time in an atmosphere that contains this gas. This gas irritates the upper respiratory system. FILL IN THE BLANKS A PERSON IS NOT LIKELY TO REMAIN IN AN ATMOSPHERE CONTAINING BECAUSE IT IS AN EXTREME IRRITANT AND EASY TO DETECT. Answer: sulfur dioxide 31D At Tow concentrations hydrogen sulfide, however, is a colorless, toxic, flammable gas that has an odor of rotten eggs. It is also an irritant and is heavier than air. Unfortunately, prolonged exposure to hydrogen sulfide tends to dull the sense of smell. Therefore, a miner should not rely fully on the sense of smell for detection of this gas. Hydrogen sulfide has a thresh- old Timit value of 10-parts-per-million of air and forms flammable mixtures (with air) over the concentration range of 4-to-44-volume percent. It is formed when blasting for sulfide ores and occurs in some natural gas, oil, and coal fields. Inhalation of high concentration of this gas causes paralysis of the respiratory system and almost sudden death. FILL IN THE BLANKS PROLONGED EXPOSURE TO MIGHT DULL AN INDIVIDUAL'S SENSE OF SMELL AND DETECTION LEADING TO DEATH. Answer: hydrogen sulfide 211 32D Usually gases are not found by themselves but are found in mixtures which make their detection more difficult. The mixtures of these gases have been rather unique names. Firedamp is a mixture of methane and traces of other gases found in the air. Afterdamp is the gaseous products and smoke produced by a fire or explosion. Afterdamp consist of carbon monoxide, car- bon dioxide, water vapor, nitrogen, oxygen, hydrogen, and hydrocarbons. Blackdamp occurs in oxygen-deficient atmosphere and is composed of carbon dioxide and nitrogen. Rock gas is another carbon dioxide and nitrogen mix- ture which creates an oxygen-deficient atmosphere. Normally, however, this particular gas mixture enters the mine from the adjacent rock strata at ordinary atmospheric pressures. FILL IN THE BLANK THE FACT THAT GASES ARE OFTEN FOUND AS MAKES THEIR DETECTION EVEN MORE DIFFICULT. Answer: mixtures 33D Smoke is another air contaminant. It consists of very small particles that often originate from the combustion or incomplete combustion of carbon- containing materials such as coal. Although smoke may irritate the nose and throat when inhaled, it is normally not considered to be an asphyxiating material. However, smoke may mix with gases such as carbon monoxide and other vapors produced by a fire making it dangerous for a person to inhale. 34D There might be a time when you find yourself in an area that is not well ventilated. Abandoned areas should be approached with care. These areas may be structurally unsafe, as well as oxygen deficient. In addition, large amounts of methane may have collected; carbon dioxide and hydrogen sulfide may have accumulated near the mine floor; and hydrogen sulfide may also have collected in stagnant ground water. Other dangerous gas mixtures may also have formed. Whatever the situation, lack of air movement is one clue that harmful gases may have accumulated. To prevent being caught unaware by dangerous gases, continually check the mine atmosphere with a gas detector or flame safety lamp. Be prepared to use your self-rescuer if a dangerous situation develops. 212 34D If you must work in areas containing dangerous gas, you should use a gas mask or respirator. Gas masks provide protection from limited concentrations of harmful gases but cannot be used safely in an oxygen-deficient area. If there is not at least 19.5 percent oxygen in the atmosphere, you need a res- pirator that supplies pure air or oxygen. FILL IN THE BLANKS ABANDONED AREAS SHOULD BE APPROACHED WITH GREAT CARE BECAUSE HARMFUL MAY HAVE COLLECTED IN THE AREA OR THE AREA MIGHT BE Answer: gases, oxygen deficient 35D The chance that any of these gases will accumulate to a dangerous level is reduced by mine ventilation. Your responsibility as a miner requires you to see that good ventilation is maintained. Because ventilation is the pri- mary means of preventing accumulation of dangerous levels of mine gases, putting equipment where it might block the flow of fresh air may create a hazardous situation. Monitoring the environment using gas detectors or a flame safety lamp assures that proper ventilation is occurring. On the rare occasion you may need to use a personal protective device, such as a self- rescuer, it must be kept in mind that it does not provide a source of oxygen. The self-rescuer is for emergency escape only and the oxygen level must be greater than 16 percent for it to be effective. In short, all underground workers must be aware of the hazards associated with mine gases, and they must take all the necessary precautions to prevent the creation of abnormal conditions. However, when such conditions exist, they should be able to recognize them and take the necessary steps to protect themselves and their co-workers. FILL IN THE BLANKS THE COLLECTION OF DANGEROUS GASES CAN BE REDUCED BY MINE AND ALL WORKERS MUST BE CAREFUL NOT TO PUT EQUIPMENT WHERE IT BLOCKS THE FLOW OF ‘ Answer: ventilation, fresh air 213 36D The following information might be helpful as a review of the gases we have discussed. Gas Air Nitrogen Oxygen Carbon Dioxide Methane Carbon Monoxide Nitric Oxide Nitrogen Dioxide Sulfur Dioxide Hydrogen Sulfide Hydrogen Symbol N2 02 C02 CHa co NO NO2 S02 H2S H2 19.5 5000 50 25 5 Ceiling Value 5 10 Hazard at elevated pressure simple asphyxiant at elevated pressure affects respiration flammable/simple as- phyxiant very toxic very toxic very toxic very toxic very toxic flammable/simple as- phyxiant 37D LET'S PAUSE AND REVIEW WHAT HAS BEEN COVERED TO THIS POINT IN SECTION D. 1. UNSAFE ACTS OR CONDITIONS ARE CLASSIFIED AS OF ACCIDENTS WHILE POOR MANAGEMENT POLICIES AND DECISIONS OR ENVIRON- MENTAL FACTORS ARE IDENTIFIED AS THE ACCIDENTS. OF 2. A SUCCESSFUL ACCIDENT PREVENTION PROGRAM REQUIRES THE OF ALL EMPLOYEES. AND 3. THE MAJORITY OF MINING FATALITIES OCCUR IN THE OF MINES. 214 10. 11, 37D TRUE/FALSE - UNDER THE FEDERAL MINE SAFETY AND HEALTH ACT OF 1977, MINE OPERATORS CAN OBTAIN VARIANCES FOR HEALTH HAZARDS. AIR NOT ONLY SUPPLIES BUT IT IS ALSO USED TO HARMFUL GASES. A FLAME SAFETY LAMP WILL CONTINUE TO BURN IN AN ATMOSPHERE THAT A. CONTAINS LESS THAN 16 PERCENT OXYGEN B. HAS MORE THAN 16 PERCENT OXYGEN C. CAUSES UNCONSCIOUSNESS DUE TO LACK OF OXYGEN D. CONTAINS NO OXYGEN EXCESS AMOUNTS OF NITROGEN IN A MINE ATMOSPHERE CAUSES A. EXPLOSIONS B. OXYGEN DEFICIENCY C. FIRES D. NONE OF THE ABOVE A GAS THAT HAS NO LOCALLY IRRITATING EFFECTS, IS LIGHTER THAN AIR, FLAMMABLE, AND IN SUFFICIENT AMOUNTS DECREASES THE OXYGEN-CARRYING CAPACITY OF THE BLOOD IS ‘ THE MOST COMMON FLAMMABLE GAS FOUND IN COAL AND OTHER ROCKS CONTAINING COMBUSTIBLE MATERIAL IS . OXIDES OF NITROGEN ARE FORMED BY A. DIESEL ENGINES B. BLASTING C. GASOLINE ENGINES D. ALL THE ABOVE E. NONE OF THE ABOVE AN INDIVIDUAL'S SENSE OF SMELL CAN BE DULLED BY PROLONGED EXPOSURE TO 215 37D 12. THE GASES AND SMOKE PRODUCED BY FIRES AND EXPLOSIONS IN THE MINES CON- SISTING OF CARBON MONOXIDE, CARBON DIOXIDE, NITROGEN, OXYGEN, HYDROGEN, HYDROCARBONS, AND WATER VAPOR IS 13. MIXTURES OF CARBON DIOXIDE AND NITROGEN IN AN OXYGEN-DEFICIENT ATMOS- PHERE IS CALLED A. AFTERDAMP B. BLACKDAMP C. FIREDAMP D. ROCK GAS 14. A HELPFUL CLUE THAT MAY INDICATE HARMFUL GASES HAVE ACCUMULATED IN AN UNVENTILATED OR ABANDONED AREA IS 15. THE PRIMARY MEANS OF PREVENTING THE ACCUMULATION OF DANGEROUS MINE GASES IS indirect causes, basic causes cooperation, support underground areas false oxygen, remove Answers: b carbon monoxide methane d 11. hydrogen sulfide 12. afterdamp 13. “b 14. lack of air movement 15. ventilation If the correct answers to the review questions were not clear, review before moving ahead. The remainder of the course will deal with radiation, heat stress, illumination, noise, dust, and ergonomic factors found in the mining industry. 216 38D Radiation Radiation, especially in uranium mines, presents to the worker a hazard that cannot be seen. It is a hazard that also cannot be detected by feel, smell, sound, or taste. Many people know mining is a hazardous job. However, few people are aware of the deaths from Tung cancer among miners affected by airborne radiation, which cause can always be traced to uranium and thorium minerals. Aside from the few exceptions of small amounts of radioactive gases that seep through water and cracks in the earth, there are no high levels of radiation in the coal mines of this country. The major radiation source and potential hazard in coal mines and other mineral processing plants and mills comes from nuclear gages. These gages are designed to generate radiation for the purpose of monitoring a particular industrial process. TRUE OR FALSE RADIATION IS ONLY A HAZARD IN URANIUM MINES. Answer: False 39D Radioactive gases in a uranium mine, for example, even in small doses, can become a serious health hazard. This hazard is usually created by radon daughters. These radon daughters become attached to the airborne dust in the mine air, and as a result, airborne radiation is produced that can be inhaled by the workers. FIGURE 6D. AIRBORNE RADIATION HAZARD 217 39D This form of energy once inhaled, is absorbed by the body cells and fre- quently causes changes to occur within the cells which eventually lead to can- cer. As a result, these cells no longer function normally after becoming cancerous. In fact, the most prevalent cause of death due to radiation among miners is lung cancer which can result from such exposure. FILL IN THE BLANKS THE MAIN CAUSE OF MINING DEATHS DUE TO RADIATION IS WHICH RESULTS FROM THE OF CONTAMINATED RADIOACTIVE DUST. Answer: Tung cancer, inhalation 40D There is an additional hazard related to lung cancer among miners who are exposed to radiation. Those workers who are exposed to hazardous levels of radiation and who also smoke cigarettes on or off the job are about 10 times more likely to get Tung cancer. Lung cancer related to radiation in mining occurs 6 or 7 years earlier among those who smoke. However, most lung cancer deaths among miners occur 10 or more years after they started working in the mine environment. FILL IN THE BLANKS A HUMAN BEHAVIOR THAT INCREASES THE LIKELIHOOD OF LUNG CANCER BY 10 TIMES AMONG MINERS EXPOSED TO RADIATION IS ‘ Answer: cigarette smoking 41D Measuring this radiation in a mine can be accomplished by using an air- sampling pump 1ike the one pictured in Figure 9C. This instrument draws air through a filter on which the airborne radioactive particles collect. The trapped particles, containing the daughters, are then counted using accurate instruments. Thus the level of radiation is determined. A special unit, called working level month (WLM), is used to calculate a worker's exposure to airborne radiation. Exposure to radiation involves two measurements, the level of radiation and the length of exposure in terms of time: (radiation level) x (time) = exposure. 218 41D This formula indicates that a person should not spend too much time in areas where high levels of radiation are known to exist. By the same token, if the levels of radiation are Tow, a person may be able to work safely with- out worrying about the time. FILL IN THE BLANKS ONCE A RADIATION SAMPLE IS OBTAINED A SPECIAL FORMULA CALLED A IS USED TO EXPRESS EXPOSURE LEVELS. Answer: working Tevel month (WLM) 42D Studies of uranium miners have shown that when the total exposure of a person exceeds 120 working level months, the person is more likely to get lung cancer. Assuming that individuals work 30 years, the maximum dose can be calculated: (120WLM) + (30 years) = 4WLM per year The present health standards state that individual exposures should be kept below the maximum allowable dose - that is below 4 WLM in any calendar year. CIRCLE THE CORRECT ANSWER WHICH OF THE FOLLOWING MEASUREMENTS WOULD INDICATE THE MOST HAZARDOUS RADIA- TION CONDITION? A. 3 WLM 4 WLM C. 2.7 WLM D. 5.5 WLM Answer: D 219 43D Uranium mines, and other mines where high levels of radiation are ex- pected to be a problem, should be developed in a special way to reduce employee exposure to radiation. These mines should have a ventilation system capable of delivering uncontaminated air to the work areas. In fact, the only practical and legally acceptable method of controlling radiation is by ventilation. Ventilation should provide not only enough air but air that is of a high standard of quality for the workers. Circulation is of primary importance and neglecting to close doors, hang curtains properly, or prevent obstructions by equipment, only increases your chances of exposure to radia- tion and mine gases. FILL IN THE BLANK THE MOST ACCEPTED METHOD USED FOR THE CONTROL OF RADIATION HAZARDS IS Answer: ventilation 44D In order to prevent employee exposure to radiation in an emergency situ- ation, air purifying respirators should be used. Such an emergency might occur if employees find themselves working in poorly ventilated areas for short periods of time. An emergency situation might also exist if workers are required to enter abandoned mine workings. Remember though, respirators designed only to filter out particulate radiation do not stop radioactive gas from entering the lungs. 45D Radiation is indeed a health hazard found in certain mining operations. Cancer of the lungs may be caused by occupational exposure to airborne radi- ation in mines and mills. However, the risk of this fatal disease may be tenfold for those who smoke cigarettes. Effective ventilation can maintain the airborne radiation at the work site below the maximum allowable levels. In addition, education of employees on the hazards of ionizing radiation and cigarette smoking, along with regular medical checkups will reduce the inci- dence of lung cancer among uranium mine workers. FILL IN THE BLANKS LUNG CANCER RELATED TO RADIATION AND MINING CAN BEST BE REDUCED THROUGH ’ » AND ‘ Answer: ventilation, education, medical checkups 220 46D Heat Stress The search for new sources of minerals requires the expansion of under- ground mining in deeper, and therefore, hotter levels of the earth's crust. In mining, as in other industries, the exposure of workers to very hot con- ditions is unhealthy, unproductive, and causes workers to ignore unsafe working situations. An increased amount of heat will interfere with an individual's metabolism and cause health problems such as heatstroke, fainting, exhaustion, cramps, and dehydration or water deficiency. TRUE OR FALSE HEAT CAN IN FACT MAKE A PERSON UNAWARE OF UNSAFE WORKING CONDITIONS RESULTING IN ACCIDENTS. Answer: True 47D Generally speaking, temperatures on the job, humidity, and air movement (ventilation) can be controlled to reduce heat at the work site. However, at a point these controls fail to prevent an individual's body temperature from rising. Work practices may then be the only heat-stress control measure. Some desirable work practices to consider when working in a hot environment are: eo frequent breaks and reasonably short work periods ® pacing your work tasks e rotating personnel on hot jobs e® providing readily accessible cooler rest areas, and ccol and slightly salted drinking water. eo long-term adjustment of an individual to heat (acclimatization) FILL IN THE BLANKS IF PROPER VENTILATION IS NOT ADEQUATE TO REDUCE HEAT STRESS, PROPER MAY THEN BE THE ONLY HEAT STRESS CONTROL MEASURE. Answer: work practices 22] 48D Such things as the sun, machines, power equipment, lighting system, etc., contribute to the heat Toad in either a surface or underground mine. Also a miner's body releases a certain amount of energy in the form of heat to the mine air especially in a crowded work area. Ventilation, shielding, canopies outside, using more efficient equipment,and possibly automation could control such factors. However, education concerning the signs and symptoms of heat stress, proper first aid procedures, and techniques to reduce heat stress are perhaps a miner's best defense against this particular stress factor. FIGURE 7D. EDUCATION! FILL IN THE BLANK SHIELDING, AUTOMATION, AND MORE EFFICIENT MACHINES ARE ALL CONTROL MEASURES USED AGAINST HEAT, HOWEVER, AN INDIVIDUAL'S BEST PROTECTION IS THE RESULT OF Answer: education 222 49D Workers performing hazardous jobs while at the same time being exposed to temperatures in excess of 80 degrees are much more 1ikely to have high accident rates. Excessive physical activity in hot work areas causes in- creased stress on the human body (higher sweat and heartbeat rates). Long- term exposure of non-acclimatized persons to heat stress is both unhealthy and unproductive. Proper selection of employees, adequate time for acclima- tization of the worker, and education of people that are assigned to work in hot work sites, along with effective engineering controls of the existing heat problem, will allow for a healthier and more productive work environment. CIRCLE THE CORRECT ANSWER A BETTER WORK ENVIRONMENT UNDER HEAT STRESS CONDITIONS IS PROVIDED BY A. ACCLIMATIZATION AND EDUCATION B. ENGINEERING CONTROLS C. PROPER CHOICE OF EMPLOYEE D. ALL THE ABOVE E. NONE OF THE ABOVE Answer: D 50D Dust and Noise Two major health hazards in the mining industry are dust and noise. Both of these become more hazardous as the size and number of machines used in mining increase. First let's turn our attention to respirable dust. Respirable, if you remember, means capable of being taken in by breathing. So, respirable dust is that dust that can be breathed in. When you are working in a mine, many types of dust, including respirable dust, will be around you because all mining produces dust like that illus- trated in Figure 8D. 223 50D FIGURE 8D. MINING-GENERATED DUST Non-coal miners extracting materials such as iron, lead, limestone, talc, potash, uranium, etc., may develop silicosis. Also, miners extracting asbes- tos can develop asbestosis and possibly cancer. On the other hand, the major dust related disease developed by coal miners is pneumoconiosis (more specif- ically coal workers' pneumoconiosis, CWP, or black lung). Usually these diseases result from long-term exposure to certain dust. FILL IN THE BLANKS THE MAJOR HEALTH HAZARD IN THE MINING INDUSTRY AFFECTING THE RESPIRATORY SYSTEM IS ‘ Answer: respirable dust 224 51D When dealing with coal dust, there are two major hazards associated with its presence. The fact that it is explosive creates a safety hazard. The other is a health hazard created by respirable coal dust. In fact, as a re- sult of long periods of exposure, a miner's health may be affected so he or she may no longer be able to work in the mines or anywhere for that matter. The diseases that result might even cause death. FILL IN THE BLANKS DUST CAN BE CONSIDERED EXTREMELY HAZARDOUS BECAUSE IT CAN CAUSE BOTH AND PROBLEMS. Answer: health, safety 52D Because coal dust at a mine is a serious health and safety hazard, there are regulations regarding the amount of respirable dust in mine air. The law states that each operator of an underground coal mine shall continually main- tain the average concentration of respirable dust in the workplace in the mine during each shift to which each miner in the active workings of such mine is exposed at or below 2 milligrams of respirable dust per cubic meter of air. In a surface coal mine, exposure levels of respirable dust at each work site and installation during each shift should be at or below 2 milli- grams per cubic meter of air. 53D In regard to the explosive and fire hazard, employees must be trained to recognize and eliminate fire hazards, to evaluate and control fire, and to protect themselves and others from the hazards associated with fire. Such training should continue throughout the miner's employment and provide periodic reviews of the characteristics of fires, escapeways, emergency evac- uation plans, and the use of extinguishers and personal protective equipment. FILL IN THE BLANKS THE POSSIBLE SERIOUS RESULTS OF A FIRE OR EXPLOSIONS CAN BE REDUCED THROUGH PROPER EMPLOYEE THAT IS ASSOCIATED WITH PERIODIC OF THE CORRECT MATERIAL AND PROCEDURES. Answer: training, reviews 225 54D Generally speaking, the most effective dust control is done at the source of dust production. Water can be sprayed directly on the area where dust is created in order to reduce the amount of dust released into the air. Ventilation also reduces industrial hygiene hazards created by dust in the mining environment. Even though there are controls to Tower dust concentration levels in the mine, in some cases the amount of respirable dust in the air will still ex- ceed what the Taw requires even when controls have been used. In cases like that, you will need to wear respiratory equipment while you work. CIRCLE THE CORRECT ANSWER CONTROLS USED IN THE PREVENTION OR REDUCTION OF RESPIRABLE DUST INCLUDE A. AVOIDANCE B. VENTILATION AND WATER C. RESPIRATORY EQUIPMENT D. ALL THE ABOVE E. BAND C Answer: E 55D Thus far we have stated that ventilation is a method used to reduce dan- gerous exposure to mine gases, radiation, and dust. However, ventilation does not just mean providing the mining area with clean air. Equipment, especially operators' cabs of surface mining equipment, should also be well ventilated. This equipment should be ventilated so that dust or gas is not permitted to enter the cab area making the air dirty and hazardous. Equipment which produces large amounts of heat should also be ventilated to prevent the buildup of heat or gas which could cause a fire or explosion. Most equipment manufacturers do take the necessary steps to provide for proper ventilation in the design and production of their equipment. Problems usu- ally arise when someone tampers with the equipment or uses it improperly. 226 55D FILL IN THE BLANKS VENTILATION OF EQUIPMENT IS DESIGNED TO PROVIDE FOR AND REDUCES THE BUILDUP OF OR a Answer: clean air, heat, gases 56D Miners by the nature of their job are also frequently required to work around high noise levels. Noise therefore becomes an industrial health hazard of the mining industry. Miners in fact are constantly exposed to machinery noise from drills, shuttle cars, roof bolters, continuous miners, man trips, loaders, cutters, tractors, shovels, draglines, etc. Unfortunately, miners exposed to a Tot of noise over long period of time seem to get used to hear- ing it. However, they are actually hearing less of the noise (going deaf). This fact makes noise a somewhat ignored health hazard. After an hour or so a miner becomes accustomed to the noise of his or her drill, continuous miner, or roof bolter, and does not realize that hearing is slowly being damaged. FILL IN THE BLANK BECAUSE YOU FEEL YOU ARE BECOMING ACCUSTOMED TO NOISE ON THE JOB, NOISE IS CONSIDERED TO BE AN HAZARD. Answer: ignored 57D The intensity of sound is the pressure that is made when sound is pro- duced and it is expressed in units called decibels. Miners, in fact, should not be exposed to more than an average of 90 decibels of noise over an 8-hour shift. Certain types of sound, however, do more damage than others. High frequency sounds are the most damaging and a very harmful combination is a high frequency sound with lots of intensity. (See Figure 9D) 227 57D a) 1. FREQUENCY ) 2. INTENSITY 77) FIGURE 9D. FACTORS THAT AFFECT HEARING To you this means the highest intensity sounds are the noisiest. FILL IN THE BLANKS THE TWO MAIN FACTORS OF NOISE THAT HAVE A DIFFERENT EFFECT ON AN INDIVIDUAL'S LEVEL OF HEARING ARE AND Answer: frequency, intensity 58D Sounds differ in intensity and frequency. There can also be various sources for sound. As a result, sound affects an individual's hearing differently. Not all noise causes permanent damage. Your ability to hear depends on a number of things: the level and type of noise, the length of time you are exposed to the noise, the physical condition of your ears, and your age. Brief exposure to loud noise produces only a temporary loss. Hearing in this case can be regained after a short period of time. On the other hand a loud 228 58D continuous noise, such as that of a continuous miner, causes a gradual loss of hearing. This type of hearing loss over a period of time destroys the nerves of the ear, as a result the hearing loss can never be corrected. Impact and impulsive noise, such as an explosion, can rupture the ear- drum or parts of the inner ear. Hearing loss due to this type of noise can sometimes be corrected by surgery or with hearing aids if the ear does not fully repair itself. TRUE OR FALSE THE EFFECTS OF SOUND CAN EASILY BE PREDICTED FOR ALL INDIVIDUALS. Answer: False 59D As we have discussed, noise can cause hearing loss. But this is not the only damage it can do. Prolonged exposure to noise can also affect the human circulatory system, causing constriction of the arteries, an increased rate of heartbeat, and an increased flow of adrenalin into the bloodstream. It has also been discovered that noise affects the nervous, endocrine, and re- productive systems, and it may even damage unborn children. 60D On the job, the most noticeable effect of noise will be that it inter- feres with your ability to hear and to be heard. A noise that is not intense enough to cause hearing damage may still disrupt on-the-job communication and keep you from hearing other sounds that you wish to hear such as commands or danger signals. This inability to hear commands or danger signals may also increase your chances of having an accident. Noise on the job may also be annoying as well as make you tired. This also increases the probability that you will be careless and have an accident. FILL IN THE BLANK NOISE NOT ONLY RESULTS IN HEATING LOSS BUT ALSO INTERFERES NOTICEABLY WITH Answer: communication 229 61D Perhaps you are asking what can be done about noise? Regulations re- quire that noise measurements be taken at prescribed intervals. These measurements are taken by trained personnel and the results should be of interest to you. Engineering controls can be used to reduce sound through changes in the work environment. This is done by using sound absorbing material and re- designing and maintaining the workplace and the machines workers use. As a result sound intensity can be reduced. Management can also help control noise through administrative controls. For example, a miner who is working in a relatively noisy area might on occasion work a different job. The decision to move the miner is made by someone in the administration. Ear protection can also be used to control noise. Personal protective equipment can thus be used to help control noise. FILL IN THE BLANKS WAYS OF CONTROLLING NOISE CAN BE PLACED INTO THREE DIFFERENT CATEGORIES WHICH ARE v » AND . Answer: engineering, administrative, ear protection 62D Although there are many ways that noise can be controlled in the mine, probably the best way to do it is to get at the source of the noise. In and around the mine, most noise is caused by machinery. There is Tittle you can do to make an explosion quieter, but since you generally know when it will be set off, you can take precautions against it. However, what can be done about the noise made by machinery? Equipment noise can be reduced by lubricating noisy parts, replacing worn parts, muffling a noisy exhaust, or by making sure machine parts are mounted and balanced properly. You can also control noise by enclosing, baffling, or screening the noise source from yourself and others. FILL IN THE BLANK THE BEST PLACE TO ATTACK A NOISE PROBLEM IS AT THE OF THE NOISE ITSELF. Answer: source 230 63D In the mine, people may tell you all kinds of stories about the so-called hazards of protective hearing devices. No doubt someone will tell you that hearing protectors keep you from hearing such important sounds, commands or warnings, horns, or backup signals on trucks. Sometimes though you will lose your hearing temporarily if you are exposed to a loud noise. So even after a noisy piece of equipment is turned off, an operator who was not wearing an ear protective device may not be able to hear these sounds for awhile. The length of this could be minutes--or even hours. However, the machine opera- tor who was wearing hearing protectors, would be able to hear these sounds the moment he or she removed their ear protection. Therefore, do not be put off by those who say muffs are hazardous. If you have them or can get them, wear them when you are working around noisy machinery. TRUE OR FALSE WEARING EAR PROTECTION CAN HELP PREVENT TEMPORARY HEARING LOSS AND IN FACT AID COMMUNICATION IN CERTAIN SITUATIONS. Answer: True 64D Indeed two of the major health hazards in the mining industry are dust and noise. MWe said that of all types of dust found in mines, respirable dust is the most hazardous to your health because it can be breathed in. We men- tioned several diseases that are caused by long exposure to respirable dust. One of these diseases caused by coal dust is black Tung. We also said that respirable coal dust can also cause other health probiems. The basic health hazard of noise is that it can affect your hearing. It can also affect your ability to do a good job by interfering with on-the-job communication. Sometimes noise can even make it more 1ikely that you will have an accident in the mine. FILL IN THE BLANKS DUST IS HARMFUL TO YOU BECAUSE IT CAN BE » WHILE THE BASIC HAZARD OF NOISE IS THAT IT AFFECTS YOUR . Answer: breathed in, hearing 231 65D Both dust and noise can be harmful to your health. So remember, if you are in a situation where wearing a respirator or an ear protective device is called for--WEAR IT. Others may try to tell you that these devices are just a nuisance. However, you know better--respirators and ear protective devices safeguard your health. Remember, personal protective equipment is used in many accident prevention programs to protect workers from hazards that cannot be controlled by other means. Hazards are not eliminated through the use of personal protective equipment, but these devices serve to shield the worker should an unplanned release of energy or hazardous material occur. 66D Skin Disease When considering the agents that cause dermatitis, 80 percent of the problem comes from chemicals. The best defense in any industrial environment is to change the process or materials, thus eliminating the irritating sub- stances. If this is not possible, much can be done to enclose or remove dermatitis-causing substances before they reach the employee's skin. Education and enforcement can also provide work methods that will reduce contact with irritants. Also, personal protective equipment, well made and well selected, provides a final barrier in those cases where other methods are not totally effective. Finally, personal cleanliness provides a major defense even after contact is made with a dermatitis-causing substance. The fight against industrial dermatitis includes all five of these preventive and protective efforts. COMPLETE THE FOLLOWING SENTENCE THE SUGGESTED METHODS FOR FIGHTING AND PREVENTING DERMATITIS INCLUDE: » AND Answer: changing the process or materials, enclosing or removing the dermatitis-causing substance, education and enforcement, personal protective equipment, personal cleanliness. 232 67D I1lumination and Ergonomics Poor visibility is a mining hazard which especially exists in under- ground mine areas. Although surface miners must deal with the darkness of night and bad weather, the dangers of personal injury and equipment damage are increased underground where visibility is totally dependent upon mine illumination (artificial lighting). Poor visibility underground can be re- duced by adequate illumination. Due to the ever-changing underground mining environment, it is necessary that underground lighting instruments be portable. Also, Tights taken into or out of the last open crosscut, in return airways, and within 150 feet of a retreat area must be explosion proof. FILL IN THE BLANKS UNDERGROUND MINE ILLUMINATION MUST BE ’ » AND PROVIDE LIGHT. Answer: portable, safe, adequate 68D Underground lighting produces another problem, glare. Glare can be painful and may even cause permanent blindness. Temporary blindness, a more common occurrence resulting from glare, is caused by looking directly into the beam of light coming from a piece of machinery or cap lamp shining di- rectly into your eyes. The real danger of glare is that the effects of it is cumulative, and leads to Tong-term, harmful effects on a miner. Glare, in fact, can gradually cause permanent damage to your vision over long periods of time. 69D Glare can be decreased by reducing contrast or using dimmer lights. In- creasing illumination by rock dusting the roof and ribs of a mine also reduces glare. Refer to Figure 10D which illustrates the rock dusting procedures. 233 69D FIGURE 10D. ROCK DUSTING Equipment painted in bright colors will also improve illumination as well as the visibility of the machine. This is the reason you will see most mine machines painted yellow or orange. FILL IN THE BLANK USING DIMMER LIGHTS AND ROCK DUSTING WILL AID IN REDUCING THE HAZARD OF IN A MINE. Answer: glare 234 70D Not enough illumination is also a problem that is just as common as the problems produced by too much illumination. A dim cap lamp or burnt out head- light lengthens the amount of time you have to react to potential dangers and hazards. Often when the lighting is poor, you do not have enough time to react to danger. You may not even be able to see that there is a problem. Improving mine illumination is, therefore, important and can be accom- plished by making sure the working area and haulageways are well 1it. ITTumination of stationary hazards, such as power sources and timbers in haulageways, can be accomplished by using reflectors. All machinery lamps should also be working and your cap lamp should be cl2an and throwing a strong beam of light. However, try not to blind anyone with your cap lamp or machinery lights. TRUE OR FALSE POOR ILLUMINATION IS DANGEROUS DUE TO THE FACT IT LENGTHENS THE TIME YOU HAVE TO REACT TO HAZARDOUS CONDITIONS. Answer: True 71D In addition to mine gases, radiation, dust, noise, and poor visibility, ergonomic factors cause additional mining hazards. Working in unnatural positions, doing repetitive jobs, or lifting objects make a miner more prone to accidents. Studies have indicated that accidents occur more frequently when workers are tired and less alert as a result of exertion and stress. Two ways to prevent or reduce exertion or stress are: e 1ift with the Tegs bent and the back straight; eo after working in one position for some time, attempt a different position and stretch or exercise in the opposite direction for a few moments. Ergonomics factors do play a role in mining. For example, painting equipment bright colors makes it easier to see and recognize, reducing not only eyestrain and glare but also brain strain. Therefore, since a safe working environment is so important in underground mines, every possible action that cuts down ergonomic stresses must be taken. This is especially true in view of the fact that most injuries are due to human mistakes. 235 71D TRUE OR FALSE ERGONOMICS FACTORS THAT ARE NOT CONTROLLED CAN PLAY A ROLE IN THE INCREASED OCCURRENCES OF ACCIDENTS IN A MINE. Answer: True 72D Inattentiveness is the most common human error. Inattentiveness may re- sult from ergonomic stresses like fatigue, boredom, monotony, and discomfort from awkward equipment. For example, if equipment controls are not clearly marked, the operator might give more attention than necessary to the controls and may be distracted from the movement of the machine or miners working nearby. Also, if the operator's position is uncomfortable, the chances of injury or strain of the musculo-skeletal system increase. Indeed large-scale accidents involving other miners may result if the operator is tense instead of relaxed and alert, ready to react to emergencies. FILL IN THE BLANKS » THE MOST COMMON "HUMAN ERROR," MAY RESULT FROM FATIGUE, BOREDOM, MONOTONY, AND DISCOMFORT FROM AWKWARD EQUIPMENT. TO BE BEST PRE- PARED FOR EMERGENCY SITUATIONS, THE MACHINE OPERATOR MUST BE AND . Answer: inattentiveness, relaxed, alert 73D The results of boredom are much Tike those of inattention. A bored worker thinks about what he would rather be doing instead of his present task. This also cuts down on the time necessary to react in case of emer- gency. Boredom may even cause the emergency. Miners must be alert at all times to keep from injuring themselves and others. FILL IN THE BLANKS ALSO REDUCES THE TIME A MINER HAS TO REACT TO AN Answer: Boredom, emergency 236 74D Other Safeguards At times, the not to friendly environment of the mine has made the miner aware of his need to be sure that his own body is properly protected. Loose fitting clothes should not be worn. Safety helmets and steel-toed shoes are mandatory. Goggles should be worn when working where objects may fly into the air. Sharp or rough materials should be handled with gloves to prevent cuts and infections. At times as a result of using this equipment you may consider yourself to be a strange looking creature. However, it is better to be a safe creature than an injured, diseased, or dead one. TRUE OR FALSE YOUR PERSONAL ATTENTION TO SAFETY AND THE PROPER USE OF PERSONAL PROTECTIVE EQUIPMENT DECREASES THE POSSIBILITY OF INJURY, DISEASE, OR EVEN DEATH. Answer: True 75D Since machinery failures can cause serious accidents, operators should be trained in proper operating procedures for both normal and emergency situ- ations. Another safeguard is having machines maintained in the best condi- tion. This will mean fewer breakdowns, thus reducing the probability of an accident. Quality maintenance will also be worthwhile because fewer repairs will be needed. FILL IN THE BLANKS TO REDUCE INJURIES FROM MACHINERY BREAKDOWNS, OPERATORS SHOULD BE TRAINED IN PROPER FOR BOTH AND SITUATIONS. Answer: operating procedures, normal, emergency 76D Perhaps one of the least thought about yet most used safeguards, prac- ticed especially in underground mines, is monitoring others and letting yourself be monitored. It takes no special equipment. Merely telling other miners where you are going and how long you will be gone is a good safety habit. If you should get into trouble and not be able to signal for help, someone will be checking for you when you do not return on time. Also, equipment operators will know where to expect you if they must work or travel near you. 237 76D COMPLETE THE FOLLOWING SENTENCE ONE OF THE LEAST THOUGHT ABOUT SAFETY PRACTICES IN UNDERGROUND MINES IS Answer: knowing the location of others as well as letting others know your location 77D Most accidents and health hazards can be prevented. However, an effec- tive accident prevention and industrial hygiene program requires the complete support and cooperation of all employees--from top management down to the in- dividual worker. Top management must develop a suitable safety and health policy (preferably in writing), furnish a safe and healthful workplace, set production goals with safety and health in mind, obtain suitable equipment and supplies, assign specific responsibilities at each level of authority, and hold individuals accountable for their actions. Each manager and first line supervisor must assume responsibility for their group, establish safe procedures, and conduct periodic inspections, safety meetings, training ses- sions, and investigations. In addition, each must keep accurate records of training, incidents, accidents, inspections, and of corrective actions taken to eliminate unsafe acts and conditions. Finally, each employee must develop a safety and health awareness and become familiar with the surroundings, the established rules, the hazards associated with each procedure (routine and emergency), and the proper use of handling of the equipment and supplies with which they work (including personal protective equipment). In addition, the worker must attend all required training sessions and safety meetings, and must protect themselves and their fellow workers in the event of an emergency situation. TRUE OR FALSE DUE TO THE LACK OF ACCIDENT PREVENTION TECHNIQUES, MOST ACCIDENTS ARE DIFFI- CULT TO PREVENT. Answer: False 238 78D One of the major objectives of industrial hygiene is to make the working environment, in your case the mine, as healthy and safe a working place as possible. Proper industrial hygiene reduces the possibility of unsafe condi- tions and the chances of your committing unsafe acts. Before taking the self-evaluation test for this section, read the list of industrial hygiene practices below. Monitor the area for exposure to radiation Work in well ventilated areas Wear personal protective equipment Work in properly illuminated areas Protect against noise Lift properly Prevent excessive stress and exertion Be awake and well rested to start the job Be knowledgeable about safety equipment and warning devices Use only tools, supplies, and equipment that are in good working condition and safe Take your job seriously Keep a "clean" work area Learn to do the job properly and safely Maybe you can add to the list of good industrial hygiene practices. Perhaps you've been neglecting a few of them. If so, the next time could be the Tast! You are now ready to take the self-evaluation review for the final sec- tion of the course. Answer all the questions before checking your answers. 239 79D LET'S PAUSE AND REVIEW WHAT HAS BEEN COVERED IN THE FINAL PART OF SECTION D. 1. IT IS IMPORTANT FOR YOU TO HAVE A BASIC UNDERSTANDING OF INDUSTRIAL HYGIENE BECAUSE AS A MINE WORKER YOU WILL BE EXPOSED TO: A. B. C. D. Es NOISE AND VIBRATION DUST AND GASES REPETITIVE MOTION CHEMICALS, EXPLOSIVES ALL THE ABOVE 2. RADIATION EXPOSURE IS KNOWN TO CAUSE A DREADED DISEASE CALLED AND IF A MINER EXPOSED TO RADIATION SMOKES CIGARETTES, THE LIKELIHOOD OF LUNG CANCER INCREASES TIMES. 3. THE BEST METHOD AVAILABLE TO CONTROL RADIATION IN A MINE IS BY: A. B. C. D. ISOLATION VENTILATION WATER SPRAYS PERSONAL PROTECTIVE EQUIPMENT 4. TRUE/FALSE - WORKING IN A HOT ENVIRONMENT CAN LEAD TO AN INCREASED ACCI- DENT RATE. 5. DISEASES TO THE LUNGS CAN BE CAUSED BY: A. B. POOR VISIBILITY POOR VENTILATION POOR ILLUMINATION ALL THE ABOVE 240 79D PNEUMOCONIOSIS IS CAUSED BY: A. MINE GASES B. MINE DUST C. GLARE D. ALL THE ABOVE AN EXPLOSION CAN CAUSE WHICH OF THE FOLLOWING MINE HAZARDS? A. DUST B. MINE GASES C. NOISE D. ALL THE ABOVE NOISE FROM AN EXPLOSION IS AN EXAMPLE OF: A. PERMANENT HEARING LOSS B. A CONTINUOUS NOISE C. A CONTINUOUS HEARING LOSS D. AN IMPACT NOISE HIGH NOISE LEVELS: A. CAN TEMPORARILY DAMAGE HEARING B. CAN CAUSE PERMANENT DEAFNESS C. INTERFERE WITH COMMUNICATION D. ARE OFTEN ACCOMPANIED BY VIBRATION E. ALL THE ABOVE NOISE NOT ONLY AFFECTS HEARING BUT IT ALSO INTERFERES WITH AND THE BEST WAY TO ATTACK A NOISE PROBLEM IS TO ATTACK IT AT THE 241 11, 12. 13. 14. 15, 16. 79D EIGHTY PERCENT OF ALL DERMATITIS PROBLEMS ARE THE RESULT OF EXPOSURE. GLARE IS PRODUCED BY: A. ROCK DUSTING B. EXCESSIVE ILLUMINATION C. DECREASED ILLUMINATION D. BRIGHTLY PAINTED OBJECTS IN THE MINING INDUSTRY WORKING IN UNNATURAL POSITIONS, DOING REPETITIVE JOBS, AND LIFTING OBJECTS MAKE A MINER MORE PRONE TO STRESS. FATIGUE, BOREDOM, MONOTONY, AND DISCOMFORT RESULT IN THE MOST COMMON HUMAN ERROR, . ACCIDENTS CAN BE CAUSED BY: A. POOR VISIBILITY B. POOR ILLUMINATION C. NOISE D. EXERTION AND STRESS E. ALL THE ABOVE ACCIDENTS ARE DUE TO: A. EQUIPMENT FAILURES B. UNAVOIDABLE NATURAL COINCIDENCES C. HUMAN FAILURE D. ALL THE ABOVE *U.S. GOVERNMENT PRINTING OFFICE: 1986--648-240/NP 242 79D 17. TRUE/FALSE - TELLING OTHER MINERS WHERE YOU ARE GOING AND WHEN YOU WILL RETURN IS AN EXCELLENT SAFETY HABIT. 18. ACCIDENT PREVENTION PROGRAMS REQUIRE SUPPORT FROM 19. TRUE/FALSE - A GOOD SAFETY PROGRAM IS USELESS WITHOUT INDIVIDUAL SAFETY AWARENESS. 20. THE MAIN OBJECTIVES OF AN INDUSTRIAL HYGIENE PROGRAM ARE TO MAKE THE WORK ENVIRONMENT AND Answers: 1. e 11. chemical 2. cancer, 10 12. b 3. b 13. ergonomic 4. true 14. inattentiveness 5. b 15. e 6. b 16. d 7. d 17. true 8. d 18. all employees 9. e 19. true 10. communication, source 20. healthy, safe If the correct answers to the review questions were not clear, review the Tast part of Section D before attempting to take the course examination. If you feel it is necessary, review all sections before taking the end-of- course examination. This concludes the programmed instruction course on industrial hygiene. 243 C—O ———————— V —— » w CEE. CET YR YM LAMY YC EMT WY QUESTIONNAIRE INDUSTRIAL HYGIENE FOR THE MINING INDUSTRY This questionnaire has been included to obtain feedback which will be used to improve the workbook for use by the entry-level miner. For your convenience, the questionnaire can be folded and mailed using the return address provided. No stamp necessary. Present occupation Career goal Years of work experience How many in mining What grade did you complete in school Did you attend vocational school College How many years Major area of study How many hours did it take you to complete the workbook Did you like the format Compared with a conventional text, is it better Worse About the same Was the material too basic Too difficult Just right Explain Did you use the workbook as part of a formal training program Did you need outside assistance (a text or reference material) in completing any section in this book __ Explain Did you perform the practice exercises Did you find them useful Explain Were all the sections understandable Explain What other subjects would you recommend in this format What changes would you reccmmend General Comments: 245 POSTAGE AND FEES PAID U.S. DEPARTMENT OF LABOR LAB-441 DEPARTMENT OF CONTINUING EDUCATION NATIONAL MINE HEALTH AND SAFETY ACADEMY P. 0. BOX 1166 BECKLEY, WW 25802-1166 GENERAL LIBRARY - U.C. BERKELEY BOOD9k1723