Clearance air test

A clearance air test is the last check on an abatement job. After the crew cleans, a sampler runs air pumps in the work area and a lab counts fibers. If the count is below the target, the area can open again.

EPA guidance says the test is designed to detect asbestos fibers that the cleaning did not remove. It also says samples should be taken "aggressively." Blowers and fans stir up settled fibers first, so the test reflects a worst case, not a quiet room.

This is the answer to a common client question: how do I know the asbestos is gone? You do not rely on a handshake. You rely on a written result.

Ask who will take the samples and which lab will read them. Ask whether the sampler is independent of the removal crew. Keep the report with your building records. Tests like this sit after strong containment and HEPA cleaning in the job sequence.