The short answer
Clearance testing is the independent check after mould works are finished: a visual inspection, moisture readings to confirm the source has been fixed and materials are dry, and air or surface samples compared with outdoor and unaffected areas. It should be done by someone other than the contractor who did the work.
Who books this
- Owners and insurers signing off completed works
- Property managers before re-letting
- Builders before new linings go on
Methods used
- Visual inspection
- Moisture readings against reference
- Post-works air samples
- Surface tape lifts
Why clearance must be independent
A contractor who clears their own job has an interest in the result. Testing that is separate from whoever did the works is the simplest way to make a clearance mean something to an insurer, a tenant or a buyer. Mould Testing QLD does not carry out mould removal or drying.
What a clearance checks
- Visual: no visible growth or residual dust in the work area, and containment intact if it is still up.
- Moisture: the original source repaired, and materials back to dry reference readings.
- Air: spore types and counts in the work area comparable to outdoor air and unaffected rooms.
- Surface: tape lifts from treated surfaces where needed.
The ANSI/IICRC S520 standard describes the goal of works as returning the area to normal fungal ecology. A clearance report shows the evidence for that, room by room, and says plainly if an area needs more attention.
Example air sample
Spores per m³ · bedroom vs outdoor control
Questions people ask
Can the company that did the works do the clearance test?
It is possible, but an independent test is far more persuasive to an insurer, tenant or buyer, and avoids any question of conflict of interest.
What if the clearance fails?
The report shows which rooms or surfaces did not meet the clearance criteria and why, so further work can be targeted, followed by a re-test of those areas.
References
- [1]ANSI/IICRC S520 Standard for Professional Mold Remediation (4th ed., 2024) — Institute of Inspection, Cleaning and Restoration Certification
- [2]WHO guidelines for indoor air quality: dampness and mould (2009) — World Health Organization Regional Office for Europe
Checked against these references on 2 November 2026.