Performance testing of workplace air monitors using procedures based on draft ANSI N42. 17B

The performance of commercially available continuous air monitors used in the workplace to monitor levels of airborne particulates (alpha, beta/photon emitters) was evaluated by personnel at the Pacific Northwest Laboratory. Testing procedures are based on criteria and methods in draft ANSI N42.17B, ''Performance Specifications for Health Physics Instrumentation - Occupational Airborne Radioactivity Monitoring Instrumentation.'' Testing requirements and results are discussed for the following tests: stability; effects of temperature, humidity, and ambient pressure; alarm threshold drift; coefficient of variation; response time; energy dependence; and air flow rate accuracy. Tests results show that certain systems may show large temperature, humidity, or ambient pressure effects; interference effects from radio frequency fields; very slow response times; a large beta-energy dependence; or a saturation problem in high-exposure conditions. Systems performed well when compared to stability, alarm threshold drift, and air flow rate accuracy criteria. 2 refs., 5 figs., 5 tabs.