| Abstract: | The following gas mask canister carbon fillings were evaluated in laboratory and man tests against phosphine which is finding favour as a fumigant for food stuffs: activated carbons impregnated with (1) copper sulphate, (2) potassium dichromate and silver chromate, (3) copper carbonate, potassium chromate and silver chromate and (4) potassium permanganate. Impregnation with copper sulphate (12% w/w) proved to be effective and economical. A cumulative service time of 5.2 mg h/litre was obtained in the laboratory tests at 1.7 mg/litre phosphine in air and 3.1 mg h/litre at 0.2-1.5 mg/litre phosphine in the man tests. |
