Abstract
This paper describes a method of testing laboratory fume hoods which can be used to assess their ability to provide worker protection. The method determines a hood's relative efficiency for containing a vapor released at a known rate inside the hood. Measurement of vapor contamination in the breathing zone of a mannequin standing at the face of the hood allows determination of the effects of air supply, turbulent room air, hood location, hood sash configuration or worker position on actual hood performance. Validation of the test and “protection factor” as defined for this test are presented. Test results indicate that the test method and protection factor calculation is valid for different hoods and is a valuable tool for comparison of various laboratory hood systems.