Abstract
Carbon tetrachloride has been used for years as the standard compound for evaluating the adsorption capacity of charcoal. The National Institute for Occupational Safety and Health is mandated under 42 CFR 84 to test organic vapor/gas cartridge and canister breakthrough characteristics against carbon tetrachloride. However, due to carbon tetrachloride's toxicity and potential lack of commercial availability, a substitute test agent is desirable. Screening tests employing ethyl acetate, pentane, n-hexane, and heptane have been completed and published on negative-pressure organic vapor respirator cartridges. Two test conditions (550 ppm pentane and 1000 ppm n-hexane) were selected for limited side-by-side testing with the 42 CFR 84 test criterion of 1000 ppm carbon tetrachloride. This article presents previously unpublished cartridge breakthrough time data on negative-pressure and powered air-purifying respirator organic vapor cartridges. The data were generated to establish a correlation between possible substitute test agents and carbon tetrachloride. Reproducibility data not previously reported are also presented. The results show that both pentane and n-hexane are potential replacement compounds for carbon tetrachloride. Additional work with less-adsorbent charcoals still needs to be performed.