Welding & Cutting on Painted or Coated Surfaces SWMS
Welding and thermal cutting on painted, coated, or chemically treated steel — lead paint, epoxy, zinc-rich primer and polyurethane hazards.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Welding and thermal cutting on painted or coated steel generates a complex chemical fume plume that varies dramatically with the coating system involved. Lead-based paints on older structural steel release respirable lead oxide fume, while epoxy coatings decompose into isocyanates and aldehydes, zinc-rich primers produce zinc oxide causing metal fume fever, and polyurethane finishes liberate hydrogen cyanide and toluene diisocyanate when heated above 200°C. Under WHS Regulation 2025 Part 4.1, any hot work on coated substrates constitutes hazardous chemical exposure requiring atmospheric monitoring, exposure standard compliance, and documented controls. A SWMS is mandatory because the work involves welding fume (now a confirmed Group 1 carcinogen), potential lead exposure triggering health monitoring obligations, and confined airborne contaminant generation that routinely exceeds workplace exposure standards without engineered extraction. This SWMS defines coating identification protocols, stripping requirements, ventilation specifications, and biological monitoring triggers for fabricators, boilermakers, and demolition welders working on existing painted structures.
Hazards identified
7 hazards covered, sorted by priority.
Acute and chronic lead poisoning, neurological damage, reproductive harm, and mandatory health monitoring under WHS Regulation Schedule 14
Confirmed Group 1 lung carcinogen exposure, nasal septum ulceration, and chronic respiratory sensitisation
Occupational asthma, permanent respiratory sensitisation, and lifetime exclusion from isocyanate work environments
Acute chemical asphyxiation, loss of consciousness, cardiac arrest, and death at concentrations above 50 ppm
Metal fume fever, flu-like symptoms within 4-12 hours, and repeated exposure tolerance complications
Headache, dizziness, impaired judgement increasing secondary incident risk, and chronic cardiovascular impact
Flash fire, structural damage, burn injuries, and notifiable incident under WHS Act Part 3 Division 3
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Elimination — Mechanically strip coatings 100mm minimum either side of the weld line using needle guns or grinding with HEPA-extracted shrouds before any hot work commences.
- 2Elimination — Reject hot work on unidentified coatings until XRF lead testing and SDS verification of all coating layers is documented and signed off by the supervisor.
- 3Substitution — Replace oxy-fuel cutting with cold cutting methods (saw, hydraulic shear, water jet) wherever structural geometry and access permit to eliminate thermal decomposition.
- 4Substitution — Where stripping is impossible, substitute MIG/MAG with TIG processes to reduce fume generation rate and use lower amperage parameters within procedure tolerance.
- 5Engineering — Deploy on-torch fume extraction (minimum 100 m³/hr capture velocity) connected to HEPA and activated carbon filtration meeting AS/NZS 60335.2.69 capture efficiency requirements.
- 6Engineering — Establish local exhaust ventilation with capture hood within 300mm of arc, supplemented by general dilution ventilation achieving minimum 6 air changes per hour in enclosed areas.
- 7Administrative — Conduct atmospheric monitoring per AS 3640 for lead and AS 3853 for welding fume, with results compared to workplace exposure standards and recorded for 30 years.
- 8Administrative — Implement biological monitoring (blood lead) at commencement and 3-monthly intervals where lead coatings are present, per WHS Regulation Schedule 14 health monitoring requirements.
- 9PPE — Issue powered air-purifying respirators with P3 and A2 combination cartridges (minimum APF 50) for all welders, with fit-testing per AS/NZS 1715 documented annually.
- 10PPE — Provide disposable Type 5/6 coveralls, nitrile inner gloves under welding gauntlets, and dedicated change/decontamination facilities to prevent take-home lead contamination of family members.
Applicable Codes of Practice
Mandates risk assessment, exposure standard compliance, atmospheric monitoring, and health surveillance for airborne contaminants generated during hot work on coated substrates.
Specifies coating identification, containment, stripping methodology, waste classification and worker protection requirements before welding or cutting on lead-painted steel.
Defines respirator selection based on fume composition, APF requirements, mandatory fit-testing, and cartridge change-out schedules for combined particulate and organic vapour exposure.
Governs hot work permit requirements, ignition source control, fire watch duration, and combustible coating residue management during welding operations.
High-Risk Construction Work triggered
While not categorised as HRCW under Schedule 1, lead exposure triggers mandatory health monitoring under WHS Regulation Schedule 14, and PCBU breaches attract Category 1-3 penalties — substantial and indexed; current maximum follows the prevailing WHS schedule, with worker consultation records retained 5 years and monitoring records 30 years.
Who this is for
- →Structural steel fabricators modifying existing painted assets
- →Demolition welders cutting up pre-1980 industrial structures
- →Shipyard and rail maintenance boilermakers on coated rolling stock
- →Bridge and infrastructure maintenance contractors performing in-situ hot work
What you receive
- ✓Editable DOCX template — Microsoft Word compatible
- ✓State-specific WHS legislation schedule (NSW/VIC/QLD/SA/WA/TAS/NT/ACT)
- ✓Hazard register with risk ratings + hierarchy-of-control mapping
- ✓Worker sign-on register, pre-start checklist, and incident escalation flow
Worked example
On a regional water authority project involving structural modifications to a 1970s elevated steel water tower, the lead welder pulls out this SWMS at the 6:30 am pre-start brief beside the work platform. The crew first walks through the hazard register, confirming XRF testing the previous day identified lead chromate primer and an overcoat of polyurethane finish at the cut line. The supervisor allocates roles: one welder will needle-gun strip a 150mm exclusion zone using a HEPA-shrouded tool, while a second worker tents the area with fire-resistant blankets and positions the on-torch extraction unit. Each worker initials the sign-on sheet acknowledging the PAPR requirements and confirms their fit-test currency. During the task at 10:15 am, the atmospheric monitor alarms when wind shifts reduce capture efficiency at the LEV hood. The welder stops work, the supervisor retrieves the SWMS, and the crew applies the documented adjustment protocol — repositioning the extraction arm within 200mm of the arc, increasing extraction flow, and adding a portable axial fan for dilution. The change is noted on the SWMS amendment log, workers re-sign acknowledging the modified control, and work resumes. At shift end, decontamination occurs in the documented sequence: coveralls bagged for disposal, boots wiped, hand and face wash before any food or drink, in line with the take-home contamination control referenced in the controls section.
Related legislation
- WHS Act 2011 (model)
- WHS Regulation 2025
- AS 1674 — Safety in welding; Welding Fume CoP