Gas and Vapor Sampling Methods
Sampling for gases and vapors is done to identify and quantify the amount of a pollutant in an environment. The reasons for obtaining a sample may be to assess compliance with an occupational exposure limit (OEL), to assess the health risk posed by the pollutant, to determine the efficacy of control measures for minimizing exposures, or for an epidemiological study. In this chapter, we shall discuss the various means by which gases and vapors are collected for further analysis. A gas is a substance that naturally exists in the gas phase at 760 mm Hg (101 kPa) and 20
C. A vapor is the gaseous form of a solid or liquid in equilibrium with its gas phase.