Comparison Between a Passive Organic Vapor Monitor (OVM) and a Charcoal Tube for Monitoring Benzene, Ethyl Benzene, Toluene and Xylene

Introduction Due to increased awareness of the toxicity of organic substances, government organization, such as the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH), have continually decreased the permissible exposure limits of many organic substances. For example, in the last ten years, the permissible exposure limit for benzene has been lowered from 10 to 0.1 ppm. This has lead to an increased demand for sampling methods and devices capable of measuring these low concentrations. Although passive diffusive methods have been used for more than a decade, there is still hesitation about their performance as compared to the tube/pump method.