Clearance Failure and Beard on a Half-Mask
After abatement of 800 square feet of ceiling tile, the contractor's visual inspection is clean. A PCM clearance sample from five locations gives 0.012 f/cc; the contract limit is 0.01 f/cc, and one sample is 0.018 f/cc. The specification requires aggressive sampling. The contractor wants to open the area because the OSHA PEL is 0.1 f/cc. Two workers who did final cleaning wore half-mask P100 respirators; one has a beard, and their fit tests were 14 months old. Their 8-hour TWA exposure was 0.06 f/cc. The building owner asks whether the area can be occupied, whether the workers can continue wearing the same respirators, and what records must be kept. The contractor says the clearance result is close enough because the lab limit of detection is 0.01 f/cc.
1. Interpret the clearance result against the OSHA PEL and the contract limit.
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OSHA's 0.1 f/cc PEL is a worker exposure limit for an 8-hour TWA; it is not a clearance standard. The contract requires aggressive sampling and a limit of 0.01 f/cc. The result 0.012 f/cc, with one sample at 0.018, exceeds the contract limit, so the area fails clearance even though it is below the OSHA PEL. The contractor's argument confuses the two standards. PCM also counts all fibers, not just asbestos, so the result must be interpreted with the sampling and analytical method. The area should be re-cleaned with HEPA vacuums and wet methods, then re-sampled using the specified aggressive method. Occupancy should wait until the contract clearance criteria are met.
2. Can the two workers continue using the same half-mask respirators? Explain the fit-test and exposure issues.
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The bearded worker cannot use a tight-fitting half-mask respirator because facial hair interferes with the sealing surface. A fit test from 14 months ago is also expired; fit testing is required annually before use. The 0.06 f/cc TWA is below the PEL but still requires exposure controls and, if respirators are used, a complete respiratory protection program. Options are to shave and pass a fit test, or use a loose-fitting powered air-purifying respirator with a hood or helmet, or supplied air. Medical evaluation, training, and a cartridge change schedule are required. The employer cannot rely on the old fit test or the PEL to justify the current use.
3. What records should be kept for the clearance and respirator issues?
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Keep clearance sampling records, chain of custody, calibration, analyst qualifications, and the re-cleaning and retest results. Keep respirator fit test records, medical clearance, training, and exposure monitoring for the workers. Waste manifests and landfill receipts document disposal. The owner should receive a closeout package with the clearance report, waste records, and a statement that the contract limit was met. If the area is reopened before passing, document the rationale and any corrective action; otherwise the record supports a compliance violation.