347. The disinfection of contaminated metal surfaces with hypochlorite solutions

Abstract

Tinned trays were artificially infected withStaphylococcus aureusin diluted milk and the dried surfaces disinfected by rinsing with sodium hypochlorite solutions.Under the conditions described, which we believe approximate those on many dairy utensils which have been imperfectly cleaned, thepH of hypochlorite solutions was found not to be a very important factor in determining their germicidal efficiency. AtpH 10 and 11, the solutions were equal to or slightly more efficient germicides than solutions at pH7.In the destruction of 99% of the organisms on the metal trays, a solution atpH 10, containing 200 p.p.m. available chlorine was about 7 times as rapid as one with 25 p.p.m. available chlorine.