STATE PLANT BC 
 
 UNITED STATES DEPARTMENT OF AGRICULTURE 
 B\ireau of Entomology and Plant Quarantine 
 Washington, D. C. 
 
 3. E. P. Q. U7U May 7, I93S 
 
 (Supersedes H. 3. l6l and 
 supplements P. Q. C. A. 309) 
 
 JAETHOD USED FOR THE DISINFECTION OF IMPORTED BROOMCORN AND 
 
 BR00MC0RN 3R00MS 
 
 3roomcorn and articles made of broomcorn which are required to "be 
 treated, under the provisions of regulation 5 of Quarantine No. kl t will 
 he treated by one of the following methods: 
 
 I. Vacuum Pamigation: 
 
 (1) The temperature of the stalks and of the fumigation 
 chamber during the fumigation shall be net less than 
 60 F. 
 
 (2) The dosage for the fur.i~aticn shall be 3 pounds of 
 liquid hydrocyanic acid or its equivalent per 1,000 
 cubic feet of space. 
 
 (3) The air pressure in the fumigation chamber shall be 
 reduced to the equivalent of 2 inches of mercury (a 
 28-inch vacuum at sea level), after which the hydro- 
 cyanic acid shall be introduced and the low pressure 
 held for the duration of the fumigation. 
 
 (k) The e:;posure shall be not less than 3 hours. 
 
 II. Steam Sterilization: 
 
 (1) The air pressure in the treating chamber shall be 
 reduced to the equivalent of 5 inches of mercury 
 (a 25-inch vacuum at sea level). 
 
 (2) Steam shall then be introduced until a positive 
 pressure of 10 pounds is obtained. 
 
 (3) The exposure to the 10-pound positive pressure of 
 steam shall continue for a period sufficient to 
 assure a constant temperature in all parts of the 
 treating chamber, after which the st-an nay be shut 
 off and the treating chamber exhausted of the un- 
 condensed steam. 
 
 AVERY S. HCYT, 
 Acting Chief. Bureau of Entomology and Plant Quarantine 
 
UNIVERSITY OF FLORIDA