70 ....... Revision of HGB #97 Apr. 1964, Aug 1964, Sept. 1967 Sanitation % in HOME LAUNDERING Home and Garden Bulletin No. 97 U.S. DEPARTMENT OF AGRICULTURE Sanitation in HOME LAUNDERING Prepared by Consumer and Food Economics Research Division, Agricultural Research Service Research has shown that a suitable disinfectant used during home laundering can prevent or reduce the spread of bacterial in- fections by clothing and household textiles. Sanitizing — or reducing the total number of bacteria in the fabrics to a safe level — can be done inexpensively, easily, and with- out damage to the fabric. This bulletin presents practical methods of sanitizing home laundry. It reports the use of four types of disinfectants that the U.S. Department of Agriculture found effective in killing bacteria during laundering. Such a disinfectant is often necessary because bacteria can re- main alive through home laundering. Home laundering is denned as any laundry done by the homemaker herself — whether in in- dividually owned washing machines or in machines used by several families, such as coin-operated machines. Bacteria can be transferred from one article of clothing to an- other during laundering. They also can remain alive on the inner surface of the washing machine and be transferred from one load of clothes to another. « I This makes it possible for bacteria on the clothes of one family to be transferred to the clothes of another family when a machine is used by several families. KINDS OF BACTERIA In the laboratory, clothing and household textiles of nine fami- lies were washed regularly for several months. An automatic household washer and typical home laundry methods were used, both with and without a disinfectant. Studies of the laundry show r that 30 kinds of bacteria survived. A few of these bacteria are potentially harmful. Among them are — • Staphylococcus aureus, frequently known as staph. This can cause boils, carbuncles, skin infections, respiratory infections, kidney infections, and other types of infections. • Pseudomonas aeruginosa, frequently known as the green pus producer. This can cause skin and kidney infections. It often is present in chronic infections of the middle ear. • Paracolon bacteria. Some of the bacteria in this family pro- duce intestinal disturbances. WHAT IS THE PROBLEM? Neither the water temperatures nor the detergents used under today's home laundering conditions can be relied on to reduce the number of bacteria in fabrics to a safe level. 1 Many bacteria, of course, are released from fabrics during wash- ing and go down the drain with wash or rinse water. But many others stay in fabrics. Bacteria in Washing Both time and temperature are important in killing bacteria. For example, it takes 3 to 5 minutes at 212° F. (boiling water) to kill Staphylococci, or 20 minutes at a water temperature of 140° F. But the temperature of the "hot" water used in home laundering is often less than 140° F. and wash cycles are not 20 minutes long. 1 No microbiological evaluation was made of commercial laundering. "Warm" water is approximately body temperature — 98.6° F. "Cold" water comes directly from the cold water faucet; its temperature varies with the season and geographical location. Many more bacteria survive cold water laundering than either hot or warm water laundering. Bacteria in Drying Some fabrics may contain large numbers of bacteria when they go into dryers. Automatic dryers and line drying cannot be de- pended on to kill all bacteria in fabrics, but they can be depended on to reduce the number of bacteria. Survival of bacteria varies with the size of the load, the drying temperature, and drying time. When an automatic dryer is installed, the exhaust should be vented to the outdoors. This will prevent the "atomizing" — or dispersion into the room — of bacteria released from fabrics during drying. All measures that reduce the number of bacteria in launder- ing and drying will automatically improve the sanitation of the fabrics. CAN BACTERIA BE CONTROLLED? Some homemakers became aware of the spread of bacteria by clothing and textiles when their families developed stubborn infections. The infections spread from one person to another. In response to requests from these homemakers, microbiologists of USDA's Textiles and Clothing Laboratory studied bacteria found in family laundering. Then they searched for a practical way to improve sanitation of home laundering by the use of a suitable disinfectant. A disinfectant had to meet the following criteria to be con- sidered suitable as a laundry sanitizer: • It must kill many kinds of bacteria. • It must not injure or discolor fabrics. • It must not leave a residue on clothes that is harmful to humans. • If used in the wash cycle, it must be compatible with the detergent. • It must be readily available and reasonable in cost. Researchers found that four types of disinfectants meet these requirements. WHAT PRODUCTS ARE AVAILABLE? The following products are effective for use as sanitizers in home-type laundering at hot, warm, or cold water temperatures : % Quaternary disinfectants Quaternary disinfectants are col- orLess and odorless compounds. Examples: Co-op Household Sanitizer; avail- able in certain supermarkets. Roccal Brand Sanitizing Agent; available in drugstores and from janitors', hospital, dairy, and poultry supply houses. . What to look for on the label: "Benzalkonium chloride." The products listed above also have "n-alkyl dimethyl benzyl ammonium chloride" on the label. Liquid chlorine disinfectants Liquid chlorine disinfectants are better known to homemakers as liquid chlorine bleaches. Examples: Clorox. Purex (liquid). Fyne Tex (liquid) Bleach. Hi-Lex Liquid Bleach. Texize Bleach. Red and White Brand Bleach. Available in supermarkets (or grocery stores). What to look for on the label: The label should state that it contains 5.25 percent of sodium hypochlorite. The following products are effective for use as sanitizers in home laundering at hot and warm water temperatures : I Pine oil disinfectants The pine oil odor is characteristic of pine oil disinfectants. Examples: Fyne Pyne. Fyne Tex. Pine-O-Pine. Texize Pine Oil Disinfectant Available in supermarkets (or grocery stores). What to look for on the label: The label should state that the product contains at least 70 percent steam-distilled pine oil. Such prod- ucts will not leave an odor on fabrics. Phenolic disinfectants The phenol or carbolic acid odor is characteristic of phenolic dis- infectants. Examples: Pine-Sol. Lysol Brand Disinfectant Texize 8304 Centex. Available in supermarkets (or grocery stores) . What to look for on the label: "Ortho - benzyl - parachlorophenol" or "ortho-phenyl-chlorophenol." Trade names are used in this publication solely for the pur- pose of providing specific information. Mention of a trade name does not constitute a guarantee or warranty of the product by the U.S. Depart- ment of Agriculture or an en- dorsement over products not mentioned. * USING DISINFECTANTS When there is sickness in the family or when laundry facilities are shared, USDA microbiologists suggest the use of a disinfectant in each load of laundry. In using a disinfectant in your laundry, always — • Read the label. • Follow all directions and heed all precautions. • Measure disinfectant carefully. • Add disinfectant to the recommended wash or rinse cycle. • I Quaternary Disinfectants Add quaternary disinfectants to the water at the beginning of the rinse cycle. Use the amount recommended on the label. Or add y 2 cup (4 ounces) to rinse water in a top-loading machine. Add 6 table- spoons (3 ounces) to rinse water in a front-loading machine. Liquid Chlorine Disinfectants In using a liquid chlorine disinfectant, or bleach, observe warn- ings on the bottle label. Liquid chlorine bleaches are not suitable for use on wool, silk, spandex, or certain dyed and finished fabrics. Add liquid chlorine bleach to water and mix in before putting clothes into the washing machine. If this is not possible, dilute bleach in 1 quart of water before adding it to the washer. Do not use bleach in rinse water. Use the amount of liquid chlorine bleach recommended for bleaching. Usually, 1 cup (8 ounces) is added to a top-loading machine; y 2 CU P (4 ounces) is added to a front-loading machine. Pine Oil Disinfectants Add pine oil disinfectant at the beginning of the wash cycle. If possible, pour it into the water before placing clothes in the machine. Use % cup (6 ounces) for a top-loading machine and y 2 CU P (4 ounces) for a front-loading machine. Phenolic Disinfectants Add phenolic disinfectants to either the wash or the rinse water. With a phenolic disinfectant containing approximately 3 per- cent of active ingredient, use 1 cup (8 ounces) of phenolic disin- fectant for a top-loading machine or 10 tablespoons (5 ounces) for a front-loading machine. SANITIZING HINTS Sanitize the washing machine occasionally. This will kill bacteria that live on the interior surface. Pour a disinfectant into the empty machine; then complete a 15-minute cycle at the hot water setting. Because bacteria remain alive on the fibers in the lint trap, wash the lint trap occasionally with hot water and soap or detergent. UNIVERSITY OF FLORIDA CHLORINE PHENOLIC PINE OIL QUATERNM I Sort dirty clothes and clean clothes at different times. Do not shake dirty clothes near clean laundry, or near surfaces that will later be used for sorting laundry. Shaking dirty clothes releases bacteria, which then settle on nearby surfaces. If possible, sort dirty clothes on a table or in one area ; sort and fold clean clothes on a second surface and in another area. If this is not possible, cover the table or the work area with clean paper, plasric sheeting, or any other clean material before working with clean clothes. This will prevent bacteria from being redeposited on freshly washed clothes. For the same reason, cover canvas- bottomed carts with clean paper or plastic before loading them with clean laundry. Such precautions are especially important when laundry facilities are shared. This is a QsmMJMAAXj QoXaUjW off u SDA I Washington, D.C. Revised September 1967 Slightly Revised July 1970 •frUS. GOVERNMENT PRINTING OFFICE : 1970— 0-384-448 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 5 cents