Industrial Hygiene (IH)

The IH source data with headspace characterization data can be used to identify what chemicals are likely to be present in the worker breathing zone and estimate their maximum concentrations, but worker protection must be based on actual workplace data. Workplace data can come from monitoring or sampling the worker breathing zone. Personal samples are collected to establish the time-weighted average (or other regulatory limit) concentration of vapors to which the worker has been exposed. Monitoring is conducted with direct reading instruments (DRI) and colorimetric devices (e.g., Drager tubes) that provide essentially real time field measurements. Sampling, which entails subsequent laboratory analysis of the samples, is conducted to identify and measure chemicals not specifically addressed by monitoring methods.

Area characterization data may be collected using sampling devices which have the capability of measuring the concentrations of all COPCs or through area monitoring devices capable of measuring some of the COPCs. Area characterization data are typically collected from several fixed locations considered representative of the worker breathing zone (not at sources such as the breather filter of an SST).