[The tenacity of bacteria in the airborne state. IV: Experimental studies on the viability of airborne E. coli 0:78 under the influence of different temperature and humidity].

Abstract

In a static aerosol chamber the tenacity of airborne E. coli 0:78 was determined at a permanent temperature of 22 degrees C and different relative humidities (10, 15-20, 30, 75 and 85%) and also at a permanent humidity of 30-40% and different temperatures (22, 28, 30, 34 and 40 degrees C). The greatest viability of the bacteria with a half-life-time of 390 min was found at 22 degrees C and 85% humidity. At 10% humidity the half-life-time was only 55 min. At a humidity of 30-40% the tenacity decreased from 37 to 14 min half-life-time, when the temperature increased from 22 to 40 degrees C. In preliminary examinations it could be shown that the method of cultivation and age of the bacterial suspension had an influence on the tenacity in the airborne state.