INDUSTRIAL FUMIGATION AGAINST INSECTS 



37 



FUMIGATION OF VARIOUS COMMODITIES 



Since it is impossible to discuss here in detail the fumigation of 

 all the many types of commodities that become infested with in- 

 sects, only those commodities most often fumigated in commercial 

 establishments are included in this circular. The fumigation of 

 grain in bulk on the farm and in the terminal elevator is discussed 

 in other publications of the Department. 4 Xo attempt is made to 



Figure 34. — Automatic record of four vacuum fumigations conducted during a period 

 of 24 hours. Hours of day and night are indicated on the circumference of the chart. 

 Figures in circles indicate: (1) vacuum pump started; (2) chamber exhausted to 

 28.5 inches of mercury; (3) fumigant (ethylene oxide-carbon dioxide mixture) intro- 

 duced; (4) treatment period of 2 hours; (5) vacuum pump operating and breaker 

 valve opened simultaneously, providing an air wash of product fumigated; (6) treat- 

 ment cycles similar to (4) ; (7) last fumigation of day allowed to continue over- 

 night; (8) doors opened, commodity removed, and a new lot placed in chamber; (9) 

 vacuum pump started before breaker valves were opened, accounting for the rise in 

 vacuum at this point. 



discuss the fumigation of any commodity from a quarantine stand- 

 point. For more detailed information regarding the treatment of 

 any commodity discussed in the following pages, or regarding 

 commodities not mentioned, the reader should direct inquiries to 

 the Bureau of Entomology and Plant Quarantine, United States 

 Department of Agriculture, Washington, D. C. 



4 Farmers' Bulletin 1260. Stored-Grain Pests, and Farmers* Bulletin 1483, Control of 

 Insect Tests in Stored Grain. 



