1.1 This practice describes the detection and measurement of time weighted average (TWA) concentrations of toxic gases or vapors using length-of-stain colorimetric dosimeter tubes. A list of some of the gases and vapors that can be detected by this practice is provided in Annex A1. This list is given as a guide and should be considered neither absolute nor complete.

1.2 Length-of-stain colorimetric dosimeters work by diffusional sampling. The results are immediately available by visual observation; thus no auxiliary sampling, test nor analysis equipment are needed. The dosimeters, therefore, are extremely simple to use and very cost effective.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.