After asbestos removal: air clearance and reoccupation
Removal is not the end of the process. Before you can safely reoccupy the work area, an independent UKAS-accredited analyst must carry out a 4-stage air clearance and issue a clearance certificate. This guide explains what happens at each stage and what documentation you should keep.
The 4-stage clearance process
The analyst inspects the work area for any remaining asbestos debris, dust, or residue. The area must be visually clean before the next stage can proceed. If debris is found, the removal contractor must carry out additional cleaning before the inspection is repeated.
The analyst verifies that the cleaning carried out by the removal contractor meets the required standard. This includes checking the HEPA vacuum records and damp-wipe logs. The work area must be demonstrably clean — not just visually clear.
Air samples are taken from the work area and sent to a UKAS-accredited laboratory for analysis. The samples are analysed using phase contrast microscopy (PCM) or transmission electron microscopy (TEM). The area passes if the fibre count is below the clearance indicator level (CIL).
Once the air sampling results are confirmed, the analyst carries out a final visual inspection. If all four stages pass, the clearance certificate is issued. The area is now confirmed safe to reoccupy.
Once all four stages pass: The analyst issues the clearance certificate. You can reoccupy the area immediately. The certificate is your permanent record that the area was confirmed safe.
Documentation to keep permanently
After a professional asbestos removal, you should receive and retain the following documents. Keep them together — you may need them for insurance, property sales, or future renovation work.
Issued by the independent UKAS-accredited analyst. Confirms the area is safe to reoccupy.
Identifies the ACMs found, their condition, and the recommended action. Issued before removal.
Documents the waste type, quantity, carrier, and disposal site. Required by law.
Confirms the removal was carried out by a trained and insured contractor.
From our work
The clearance that failed — and what happened next
On a commercial job in Bermondsey — a ground-floor office where Artex ceilings had been removed — the first air clearance attempt failed. The analyst found visible residue on a window ledge that had been missed during the final clean, and the visual inspection did not pass.
The removal crew returned, carried out additional cleaning, and the analyst returned the following morning. The second inspection passed, and the clearance certificate was issued. The office was reoccupied two days later than planned.
The client was understandably frustrated by the delay. But the process worked as it should: the independent analyst caught something the removal crew had missed, the crew corrected it, and the area was only cleared once it was genuinely safe. A clearance process that always passes on the first attempt is not a sign of quality — it is a sign that the bar is not high enough.
We now carry out a more rigorous internal pre-clearance check before calling the analyst, specifically targeting the surfaces — window ledges, skirting boards, and door frames — that are most commonly missed in the final clean.
Frequently asked questions
Air clearance arranged as part of every job
We arrange independent UKAS-accredited air clearance for all removal jobs. You receive the certificate as part of the package.