Abstract
Class II biological safety cabinets, normally used for low to moderate risk agents, are being recognized as providing a capability in certain laboratory and industrial situations whereby materials which are potentially hazardous to human health and/or to the environment may be controlled during routine processing thus providing personnel, product and environmental protection. As interest in these safety devices increases, so does the importance of understanding: what types of cabinets are available, how they are designed to function, their proper use, and how they may be expected to perform. A Class II Type A biological safety cabinet was challenged with Bacillus subtilis var. niger spores at line voltages from 85 to 130 volts in order to determine its performance during simulated brownout and power surge conditions. The cabinet, employing a 20.3 cm (8 in.) work opening passed both personnel and product protection tests at all voltages used. The cabinet, fitted with the 25.4 cm (10 in.) work opening passed the same tests with the exception of the personnel protection test at 85 volts. It was concluded that, when the stated motor-blower performance characteristics are provided, this cabinet design will perform its safety function over a considerable range of line voltages.