8 ANNUAL REPOBTS OF DEPARTMENT OF AGRICULTURE, 1953 
turers for preventing fermentation or "sweating" and, also, Insect 
damage. 
Nonexplosive Aerosol Formulation Developed 
A formulation for use in industrial aerosol generators, to be applied 
in warehouses for control of stored-product insects, has been de- 
veloped and thoroughly tested under practical conditions. It contains 
J<> percent of DDT, 2 percent of lindane. 5 percent of S. A. E. 50 
motor oil, and 83 percent of tetrachloroethylene. It is applied at the 
rate of 2 quarts per 100,000 cubic feet every 2 weeks for the first four 
applications and monthly thereafter. This material is not for use 
where food products are exposed. Operators have been cautioned to 
apply this aerosol from outside the building and not to expose them- 
selves unless wearing a mask and protective clothing. Four periodic 
applications of this aerosol produced an effective residue on horizontal 
surfaces. 
Flammahility of Oils and Solvents Used in Aerosol Formulations 
Determined 
Basic data were developed on the flammahility of the various 
solvents or oils that are commonly contained in aerosol formulations 
used in thermal or mechanical generators. A test procedure recently 
standardized by the Chemical bpecialties Manufacturers Association 
was used wherein the aerosol is sprayed into a drum containing an 
open flame. A swinging cover permits a nonhazardous explosion to 
take place when a flammable concentration is reached. The flammable 
concentration of 11 solvents and oils was determined individually 
when they were applied as coarse and as fine aerosols. The results 
showed that flammable concentrations of the individual materials 
ranged from about 18 to 60 times their concentration in aerosols as 
normally applied. This type of information had not been previously 
available from fire underwriters or the Bureau of Mines. 
Effectiveness of Lindane Against Stored-Tobacco Insects Studied 
Laboratory and tobacco warehouse tests have been continued in 
cooperation with tobacco manufacturers to determine the possibilities 
of using lindane sprays or aerosols for the control of the tobacco moth 
and the cigarette beetle. Both mist sprays and aerosols were effective 
against the tobacco moth, but neither form of application gave more 
sat Lsfactory control of the cigarette beetle under warehouse conditions 
than does the standard pyrethrum spray now in genera] use. No 
effect could be detected on the smoking quality of tobacco exposed to 
lindane spray- or aerosols. 
Insecticide Residues Protecl Fibers and Fabrics for Long Periods 
Hair and wool felts are still free from inject attack 1 years after 
applications of 2 percent DDT solutions or emulsions. Casein yarns 
are Still protected I years alter treatment with a 1-percent emulsion. 
Spanish tnOSS and tOW were protected 2 years, and feathers and down 
for 8 years by a 1 percent emulsion. M ilitary uniforms made of DDT- 
treated cloth resisted insect damage after l years of continuous 
