Collaborative testing of a gas chromatographic charcoal tube method for seven organic solvents.

The National Institute for Occupational Safety and Health has undertaken a program to provide reliable sampling and analytical methods for a number of industrial hygiene uses. Recommendation of methods to the Department of Labor for compliance testing and inclusion of methods in critera for Recommended Standards for Occupational Exposures are two prime areas of utilization. This paper presents the results of our initial efforts in collaborative testing. The method is a charcal tube sampling procedure and a gas chromatographic analytical technique. Samples of seven single component solvents which included benzene, carbon tetrachloride, chloroform, dioxane, ethylene dichloride, trichloroethylene, and xylene along with two solvent mixtures which consisted of a benzene-xylene combination and an ethylene dichloride-trichloroethylene conbination were tested in two phases by 15 participating laboratories. The data analysis indicates the overalll error associated with the method and identifies sources of error within each segment of the method.