Technical Guide: Air Monitoring and the Workplace Exposure Limits for Airborne Contaminants

This guide applies to occupational hygienists and other technical professionals responsible for assessing workplace exposure to airborne contaminants and determining compliance with workplace exposure limits, and also provides technical advice for employers. It explains inhalation, dermal and ingestion exposure pathways and the application of 8-hour time-weighted averages, short-term exposure limits and peak limitations. It guides users in developing monitoring strategies and plans, determining sampling populations and similar exposure groups, selecting sampling and analytical methods, conducting exposure assessments and interpreting results. Relevant persons should use it to identify when monitoring is needed, assess risks, recommend measures to eliminate or control exposure, and review monitoring results and the effectiveness of risk controls, supporting consistent, high-quality monitoring and compliance decisions in workplaces.