Ultraviolet Sterilization in Microbiological Laboratories: A Discussion of the Germicidal Protection Offered by Ultraviolet Lamps Installed in Airlocks, at Doorways, and on Ceilings of Microbiological Laboratories and Walk-in Incubators

Abstract

UV lamps were utilized in several ways in microbiological laboratories after experiments showed the radiation (2537A) to provide satisfactory inactivation of test organisms. Cultures of Serratia indica were used to determine the bactericidal effectiveness of each type of installation. Under the test conditions airlocks and doorway barriers were 92.5 to 100% effective in inactivating aerosols of the test organism. Irradiation of rooms with ceiling lamps for one hour effected an 86% decrease in normal air-borne contaminants. Bacteria and fungi in the air and on surfaces in a walk-in incubator room were reduced by a factor of 83 to 100% by the continuous burning of UV ceiling lamps. Radiant energy levels were recorded for each type of installation. A regular maintenance program and frequent cleaning of lamps is necessary. It is concluded that UV radiation can be used around doorways and in airlocks to separate areas of unequal infectious risk and to reduce the number of infectious microorganisms and general contaminants in laboratories and in walk-in incubators.