Bactericidal Efficiency of Quaternary Ammonium Compounds

A widespread public health interest in bactericidal agents has (leveloped during the past 50 years.This interest centers particularly on the disinfection of multiple-use eating and drinking utensils in the field of restaurant and hotel sanitation.Official action by the United States Public Health Service in this regard was reported in 1943 in the Ordinance and Code (1) recommended for the regulation of eating and drinking establishments.This Public Health Service Ordinance and Code provides for approved bactericidal processes for the dis- infection of multiple-service utensils as follows: (a) exposure in water at a temperature of at least 1700 F. for at least 2 minutes, or for $; minute in boiling water; (b) immersion in a lukewarm chlorine bath (hypochlorite) containing at least 50 ppm of uncombined avail- able chlorine for at least 2 minutes, or a concentration of equal bac- tericidal strength if combined chlorine compounds (chloramines) are used; (c) exposure to steam of at least 170°F.for at least 15 minutes, or at 2000 F. for at least 5 minutes, or (d) exposure to a hot air temperature of at least 1800 F. for at least 20 minutes.All of these pro-(edures must be carried out under the conditions specified to meet the requirements for each.Under (b) the Ordinance and Code also provides for the use of chem- ial bactericidal agents other than chlorine with the following specifications:1.The health officer concerned must determine that the substituted aigent is satisfactory.2. The concentration of the bactericidal agent must be measurable by a simple and accurate field test.Suitable compliance with these two requirements is essential if satisfactory results are to be obtained.