Mild Steel Welding Fume SWMS
Mild steel MIG, TIG, MMA, and flux-core welding. Iron oxide fume and manganese controls, ventilation hierarchy, RPE selection.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Mild steel welding — including MIG (GMAW), TIG (GTAW), MMA (SMAW), and flux-cored arc welding (FCAW) — generates a complex aerosol of metal oxides, gases, and ultrafine particles that is classified as a Group 1 human carcinogen by IARC (2017). Even on plain low-carbon steel, the fume plume contains iron oxide, manganese, carbon monoxide, ozone, and nitrogen oxides at concentrations that routinely exceed the Workplace Exposure Standard (WES) of 0.1 mg/m³ inhalable welding fume adopted by Safe Work Australia in 2024. Under WHS Regulation 2025 Part 4.1 (regulations 49–50 and 347), a PCBU must ensure airborne contaminant levels remain below the WES and must manage risks so far as is reasonably practicable. A documented SWMS is required because welding fume control involves multiple hierarchy controls, respiratory protection program elements, and atmospheric monitoring that workers must understand and sign onto before striking an arc.
Hazards identified
7 hazards covered, sorted by priority.
Siderosis, chronic bronchitis, and increased lung cancer risk per IARC Group 1 classification
Neurotoxicity, manganism, Parkinsonian tremor and cognitive impairment from chronic low-dose exposure
Acute pulmonary oedema, delayed chemical pneumonitis, and chronic airway hyperreactivity following exposure
Hypoxia, loss of consciousness, cardiac arrhythmia, and fatal asphyxiation in poorly ventilated spaces
Delayed pulmonary oedema 4–24 hours post-exposure, bronchiolitis obliterans, permanent lung function decline
Nasal septum perforation, occupational asthma, and Group 1 carcinogenic lung and sinonasal cancer risk
Metal fume fever with delayed flu-like symptoms, fever, chills, and respiratory inflammation lasting 24–48 hours
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Elimination — Eliminate welding where practicable by specifying mechanical fasteners, bolted connections, or pre-fabricated modular assemblies delivered to site already joined off-process.
- 2Elimination — Remove all surface coatings (paint, galvanising, primer, oil) from the weld zone by mechanical grinding back 50mm minimum before striking an arc.
- 3Substitution — Substitute MMA stick welding with low-fume MIG using metal-cored wire or pulsed GMAW transfer modes that reduce fume generation rates by 40–70%.
- 4Substitution — Replace high-manganese consumables with low-Mn filler wires (ER70S-3) where weld metallurgy permits, reducing manganese fume below ACGIH TLV of 0.02 mg/m³.
- 5Engineering — Install on-torch fume extraction (MIG gun with integrated LEV capture) capturing fume at the arc with minimum 100 L/s flow per AS 3853.1.
- 6Engineering — Provide flexible-arm local exhaust ventilation positioned within 300mm of the arc, with capture velocity verified at 0.5 m/s using a vane anemometer monthly.
- 7Administrative — Conduct atmospheric monitoring per AS 3640 within 30 days of new welding tasks and annually thereafter; maintain exposure records for 30 years per WHS Reg 50.
- 8Administrative — Rotate welders to limit individual time-weighted exposure, enforce 'no welding in confined spaces without permit' rule, and complete pre-start fume risk assessment.
- 9PPE — Issue PAPR with TM3 hood (APF 50) for all welding above WES, fit-tested annually per AS/NZS 1715, with HEPA P3 cartridges replaced per manufacturer schedule.
- 10PPE — Supply half-face P2 respirators (APF 10) only as backup for short-duration tack welding with confirmed LEV operation; never as primary control for sustained welding.
Applicable Codes of Practice
Specifies fume control hierarchy, LEV design, RPE selection, and welder health monitoring obligations directly applicable to all mild steel welding tasks.
Mandates fit-testing, APF selection matched to measured exposure, and respiratory protection program documentation required under WHS Reg 44 PPE duties.
Sets minimum capture velocity, extraction flow rates, and LEV positioning standards engineering controls must meet for FCAW and MIG fume capture.
Establishes the inhalable welding fume exposure limit triggering atmospheric monitoring, control review, and health surveillance under WHS Reg 49–50.
High-Risk Construction Work triggered
Not classified as HRCW under Schedule 1, however welding fume is a Schedule 14 hazardous chemical — PCBU must monitor, consult workers, and retain exposure records 30 years; penalties substantial and indexed under prevailing WHS schedule.
Who this is for
- →Structural steel fabricators and boilermaking workshops
- →Mobile site welders on commercial construction projects
- →Maintenance fitters in manufacturing and processing plants
- →WHS managers overseeing hot work permit systems
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
At a regional steel fabrication workshop producing structural beams for a warehouse fit-out, the leading hand opens the Mild Steel Welding Fume SWMS at the 6:45am pre-start huddle. Three MIG welders and one TIG welder are scheduled for full-shift work on 12mm plate columns. Working through the hazard register, the leading hand confirms manganese fume is the priority risk because the consumable is ER70S-6 (1.4% Mn). The team reviews controls: the two articulated LEV arms are positioned within 300mm of the arc — confirmed with a smoke pen capture test — and the on-torch extraction MIG gun is allocated to the welder working inside the column box section. The TIG welder signs onto the PAPR requirement (TM3 hood) because ozone is unavoidable on argon shielding. One welder flags that the southern roller door is closed due to wind, reducing dilution ventilation; the leading hand adjusts the SWMS on the spot by opening the door and relocating one fabrication to the eastern bay. All four welders sign the SWMS register. Mid-shift, atmospheric monitoring badges deployed under AS 3640 are checked — readings sit at 0.06 mg/m³, below WES. At smoko the leading hand annotates the SWMS with the monitoring result and the ventilation amendment, demonstrating live document control as required under WHS Reg 39.
Related legislation
- WHS Act 2011 (model)
- WHS Regulation 2025
- AS 1674 — Safety in welding; Welding Fume CoP