What is a "clearance air sample" used for?

A clearance air sample is specifically collected after abatement activities to confirm that the area is free of harmful asbestos fibers and meets the established clearance criteria. This type of sampling is a crucial step in ensuring that the remediation efforts have been successful and that the environment is safe for re-occupancy. If the sample results show that airborne asbestos levels are below the regulatory limits, it indicates that the area can be cleared for use.

In contrast, air samples collected before any abatement activities serve to establish baseline asbestos levels, while background samples are designed to understand existing pollution levels in the environment. Samples taken to assess overall air quality may include various contaminants, not just asbestos, and are not specifically tailored for confirming the effectiveness of asbestos abatement. Therefore, the primary purpose of a clearance air sample is to provide assurance that the remediation was effective, ensuring safety for those who will occupy the space.