Collaborative Tests of Two Methods for Determining Free Silica in Airborne Dust

摘要

Two methods were collaboratively tested in 15 laboratories: XRD Method--PCAM 259, Free Silica (Quartz, Cristobalite, Tridymite) in a Airborne Dust, and IR Method--Method for Infrared Determination of Quartz in Respirable Coal mine Dust. Samples for the tests were collected from aerosols prepared in a specially adapted laboratory generation system. The methods were found to be unbiased. Both remained classified as B methods under NIOSH criterion that a B method measure within 25% of the 'true' value 95% of the time, in a single laboratory.