Mould Remediation (IICRC S520) SWMS

Mould remediation conducted in accordance with IICRC S520 involves the controlled containment, removal and disposal of fungal contamination from building materials, HVAC components and contents following water damage or chronic moisture intrusion. The work routinely exposes remediators to elevated airborne spore concentrations, mycotoxins, microbial volatile organic compounds and antimicrobial chemistry, while simultaneously requiring negative-pressure containment, HEPA filtration and respiratory protection that introduces its own physiological and ergonomic loading. Under WHS Regulation 2011 r34–r38 a PCBU must identify reasonably foreseeable hazards, assess risk and implement the hierarchy of control, and where remediation forms part of structural drying, demolition or refurbishment exceeding $250,000 it is captured as construction work under r291. A Safe Work Method Statement is mandatory for any High Risk Construction Work activity and is strongly recommended for all Condition 2 and Condition 3 remediations because of the combined biological, chemical and respiratory hazards present.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Elimination — Where structurally feasible, remove and dispose of porous Condition 3 materials (gypsum, insulation, carpet underlay) off-site rather than attempting in-situ cleaning to eliminate residual reservoirs.
2. 2Elimination — Rectify the underlying moisture source and verify substrate moisture content below 16% prior to reconstruction so that recolonisation pathways are removed before clearance.
3. 3Substitution — Substitute solvent-based or chlorine-based biocides with lower-toxicity hydrogen peroxide or botanical antimicrobials carrying favourable SDS hazard classifications under the GHS 7 framework.
4. 4Engineering — Establish IICRC S520 critical barrier containment with 200µm polyethylene, decontamination chamber and negative pressure of minimum 5 Pa verified by manometer logged hourly.
5. 5Engineering — Deploy HEPA-filtered air scrubbers sized for minimum 4 air changes per hour, exhausting outside the building envelope through sealed ducting clear of intakes.
6. 6Engineering — Power all equipment through RCD-protected leads tested and tagged to AS/NZS 3760, with elevated cable management to prevent contact with extracted water.
7. 7Administrative — Conduct pre-start briefing using this SWMS, confirm Condition assessment, log all entries and exits in the containment register, and limit shifts in PPE to 90-minute rotations.
8. 8Administrative — Hold current IICRC S520 Applied Microbial Remediation Technician certification, complete annual respirator fit-testing to AS/NZS 1715, and review SDS for every antimicrobial before mixing.
9. 9PPE — Issue full-face P3/PAPR respirators, Type 5/6 disposable coveralls with taped seams, nitrile gloves over cotton liners, and chemical splash goggles where biocide spraying occurs.
10. 10PPE — Provide doffing protocol signage, single-use bootcovers, and clean-zone reissue of replacement PPE so contaminated suits never cross the decontamination chamber threshold.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a Condition 3 mould remediation at a two-storey suburban office that suffered a roof failure and prolonged ceiling cavity saturation, the lead technician opens this SWMS at the 7:00am pre-start brief in the site shed. Working through the hazard register on screen, the crew confirms the Condition assessment, the antimicrobial selected (hydrogen peroxide 7.9%) and the corresponding SDS attached to the document. The supervisor walks the team to the proposed containment footprint, points out the negative air machine exhaust route and the RCD board, and ties each engineering control on the SWMS to a physical item on site. Each worker signs the consultation register on the back page, recording their respirator fit-test expiry and IICRC AMRT number. Two hours into gross removal, the manometer alarms at minus 2 Pa because a critical barrier was breached when contents were carried out. Work stops, the supervisor reopens the SWMS at the containment integrity hazard, applies the documented stop-work and reseal procedure, repressurises to minus 5 Pa and re-briefs the crew before resuming. The amendment is noted on the SWMS revision line and initialled, demonstrating that the document is a live field instrument rather than a filing cabinet artefact.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• Managing Risks of Hazardous Chemicals CoP; Construction Work CoP