Welding Safety Guide: PPE, Fume, Hot Work & AS Standards

Welding sits at the heart of Australian fabrication, mining, construction, marine and trades work — but it carries hazards that no other workshop task brings together in one job: an electric arc hotter than the sun's surface, ultraviolet and infrared radiation, molten metal, toxic fume, flammable atmospheres, compressed gas, and open flame, all happening within arm's reach of the operator. Safe Work Australia data identifies welding as one of the higher-risk activities for both acute injury (arc eye, burns, electric shock) and long-term occupational disease (lung disease, cancers from hexavalent chromium and manganese, hearing loss). This guide is the safety hub — it covers the hazards, the PPE, the Australian Standards, hot work permits, confined-space welding, and process-specific risks. Process-by-process technique is covered in the linked guides for MIG, TIG, and the MIG vs TIG vs Stick comparison.

Welding Hazards at a Glance

Use this as a pre-job mental check. Every hazard listed has a corresponding Australian Standard or Code of Practice — the right column points to the section below for detail.

Arc Radiation: UV, IR & Visible Light

A welding arc emits the full spectrum — visible light blinding enough to read by from across the workshop, plus ultraviolet (UV-A, UV-B, UV-C) and infrared. The damage isn't always immediate, which is exactly what makes it dangerous.

Arc eye (photokeratitis)

UV-B and UV-C burn the cornea. Symptoms typically start 6 to 12 hours after exposure — a feeling like sand under the eyelid, intense tearing, light sensitivity, and severe pain that often wakes the welder at 2 or 3 am. It's usually self-limiting within 24–48 hours, but each event causes microscopic corneal damage that accumulates over a career and contributes to cataract formation in later life. A single unprotected glance at striking an arc 5 m away is enough to cause it. There is no "safe" brief exposure.

Skin burn

UV-B causes a sunburn-equivalent burn on exposed forearms, neck and ears within 10–30 minutes of arc time. Welders working close to a high-current MIG or stick arc routinely get "welder's tan" lines at the cuff and collar — visible evidence the skin is being burnt. Long sleeves, a buttoned collar, and a snug helmet that meets the jacket are the controls.

Retinal damage

Infrared radiation can damage the retina over time — different from arc eye, this is not self-repairing. Auto-darkening filters that meet AS/NZS 1338.1 are tested for IR transmission as well as visible light. A cheap or counterfeit helmet may darken visibly but pass IR straight through.

Auto-darkening helmet shade selection

Match the shade to the welding current. Going too light causes arc eye and retinal strain. Going too dark is uncomfortable but not dangerous — when in doubt, go one shade darker.

For full helmet selection — fixed vs auto-darkening, view size, grind mode, lithium battery vs solar, true-colour optics — see the welding helmet guide. For safety glasses worn under the helmet (which you still need for chipping slag and bystander protection), see the welding eye protection guide.

Warning — bystander arc eye. Helpers, apprentices, and people walking through the workshop get arc eye from the arc, not from holding the torch. Use welding screens or curtains around the work area. Anyone within 10 m of an active arc needs eye protection.

Welding Fume & Toxic Gas Exposure

Welding fume is the biggest long-term killer of welders. In 2017 the International Agency for Research on Cancer reclassified all welding fume as a Group 1 human carcinogen — confirmed to cause lung cancer in humans, with limited evidence for kidney cancer. The composition of the fume depends on what you're welding, what coatings are present, and what shielding gas you're using.

Hazardous components by parent metal

Workplace Exposure Standards (WES) — Safe Work Australia [VERIFY: check current WES values, the schedule was revised 2024]

Australian WES values for the main welding contaminants — these are 8-hour time-weighted averages unless noted:

• Welding fume (not otherwise classified): 1 mg/m³ TWA
• Manganese (Mn) and inorganic compounds: 0.02 mg/m³ TWA (respirable) [VERIFY: the 2019 reduction from 1 mg/m³ has been progressively implemented]
• Hexavalent chromium (Cr VI): 0.05 mg/m³ TWA (some references show 0.01 mg/m³ — check Safe Work AU current schedule)
• Nickel (metal & insoluble compounds): 1 mg/m³ TWA
• Zinc oxide fume: 5 mg/m³ TWA, 10 mg/m³ STEL
• Ozone: 0.1 ppm TWA (this is genuinely low — TIG in a poorly ventilated bay will breach this)
• Carbon monoxide: 30 ppm TWA

The manganese number is the one that catches workshops out. The old standard was 1 mg/m³; the current standard is 50× tighter, and routine MIG welding on mild steel without local exhaust will easily breach it. If you have welders on full shifts in an enclosed bay with no on-gun or downdraft extraction, you almost certainly have a compliance problem.

Fume controls (in order of preference per WHS hierarchy)

1. Eliminate or substitute: Can the job be done with a lower-fume process? Cold-cutting instead of plasma. MIG-brazing instead of MIG-welding galvanised. Sometimes the answer is yes.
2. Engineering controls — local exhaust ventilation (LEV): On-gun fume extraction guns (MIG), downdraft tables for bench work, fume hoods, mobile LEV arms positioned 150–300 mm from the arc. This is the primary control and should be the default.
3. General ventilation: Roller doors open, wall fans, makeup air. Not sufficient on its own, but combines with LEV.
4. Administrative controls: Job rotation, weld scheduling, training, exposure monitoring, signage.
5. PPE — last resort: P2 disposable respirator for mild steel light work; P3 reusable half-face or powered air-purifying respirator (PAPR) for stainless, galvanised, painted stock, and full-shift welders. PAPR helmets are now common and worth the investment for production welding.

Warning — phosgene. Never weld on metal that has been degreased with chlorinated solvents (trichloroethylene, perchloroethylene, "trike") without thorough rinsing and drying. The arc UV breaks the solvent down into phosgene gas. Phosgene was used as a chemical weapon in WW1. It has a faint mown-hay smell, severe pulmonary effects develop 4–24 hours after exposure, and people have died from welding on a degreaser-cleaned bench.

For respiratory selection — disposable P2, reusable half-face, full-face PAPR, supplied-air — see the respirator guide. Stock at AIMS in respiratory protection.

Burns, Spatter & Hot Metal

The spark and spatter radius around a welding arc is wider than most welders assume. Globules of molten metal from MIG and stick welding travel up to 10 m from the arc; from gouging, slag cutting, and grinding the radius is greater. The Safe Work Australia "35 ft" rule (10 m) is the international standard for hot work clearance — see the fire section below.

Clothing — what to wear and what to avoid

The clothing rules are simple and they save skin:

• Wear: Cotton drill or FR-cotton coveralls / long sleeves, leather welding jacket for heavy work, leather welding apron for bench work, leather gloves matched to the process (gauntlet cuff up the forearm).
• Don't wear: Synthetic fabrics next to the skin (polyester, nylon, fleece, polypropylene thermals). Synthetics melt when a spark lands and fuse to the skin, turning a minor burn into a major skin graft case. This includes hi-vis vests with synthetic backing — choose FR-rated hi-vis or wear it over a leather jacket only.
• Don't wear: Frayed cuffs, rolled-up sleeves, open shirt at the collar, exposed bootlaces, shorts (yes, this still happens). Cuffs that flap catch sparks like a pocket.

Glove selection by process

Footwear

Steel-cap leather work boots with covered tongues. Slip-on boots are preferred over laced for welding because laces catch sparks and burn through. If laced, run cuffs over the laces. For heavy plate work add a metatarsal guard — a 50 kg piece of dropped plate will go straight through a standard steel cap onto the foot bones. See the safety boots guide.

Electric Shock

Welders die from electric shock every year in Australia. The risk is usually under-appreciated because welding voltages feel "low" — but Open Circuit Voltage (OCV) on most machines sits at 60–100 V DC or AC, and that is more than enough to stop a heart, particularly when the welder is wet with sweat, standing on a steel deck, or working inside a tank.

Where shock happens

• Touching the electrode and the work simultaneously — completes the circuit through the body. Easy to do when reaching to reposition or changing rod.
• Damaged cable insulation — the welding lead drags across hot edges and develops splits. The split touches the welder's bare arm, the work piece earths the circuit, current flows through the chest.
• Wet conditions — sweat, rain, condensation in a tank. AS 1674.1 specifies de-rated OCV limits for wet/conductive locations: nominal OCV reduced to 12 V DC / 12 V AC peak in confined spaces and damp locations [VERIFY: confirm against current AS 1674.1 edition].
• No RCD on the supply — a residual current device trips on as little as 30 mA of leakage to earth and is the difference between a tingle and a fatality.
• Old or damaged welding machines — failed primary insulation can put 240 V mains onto the welding circuit. Annual electrical inspection and test (test and tag) of welding equipment is required.

Controls

• Inspect cables, plugs, and electrode holders before every job. Bin damaged ones — don't tape them up.
• RCD-protected supply on every welder. Most modern Australian workshops are RCD-protected at the switchboard, but verify.
• Dry intact leather gloves and dry leather boots. No bare skin between glove cuff and sleeve.
• Insulating mat or dry timber underfoot when welding on steel decks or in damp areas.
• Never change electrodes with wet gloves. Never grip the electrode by the bare metal stub.
• Voltage Reduction Device (VRD) — many modern welders have a VRD that drops OCV to ~12 V between welds. Use it, particularly in confined spaces.
• Earth (work) clamp goes onto the work piece or the bench it's clamped to — not onto pipework, structural steel, gas lines, or other equipment that the current can travel through.

Warning — confined-space welding shock risk. Inside a tank, vessel, or boiler the welder is surrounded by earthed metal in 360°, often sweating heavily, and the OCV that is mostly survivable in open air becomes a likely killer. AS 1674.1 mandates VRD-equipped machines and additional controls for these jobs.

Fire Hazards & Hot Work Permits

The fire-safety standard for welding and allied processes in Australia is AS 1674.2 ("Safety in welding and allied processes — Part 2: Fire precautions"). It is the standard your insurer's loss-adjuster will reference if a fire occurs.

The 10 m rule

Combustible materials — paper, cardboard, timber, plastics, fuel containers, dust, oily rags, packaging — must be removed from a 10 m radius around the welding work, or shielded with non-combustible covers (fire blankets, sheet metal screens). Sparks travel further than people think, particularly downward from elevated work, and a smouldering ember in cardboard or sawdust may not ignite until hours later.

Hot work permit system

For any welding, cutting, grinding, or other ignition-source work outside designated permanent welding bays — particularly in occupied buildings, on construction sites, on tanks or vessels, near flammable storage, or in roof spaces — a hot work permit is required. The permit documents: who's doing the work, where, when, what controls are in place, who the fire watch is, and when the area is signed off as cool.

AIMS has a separate detailed guide on hot work permits including a permit template — see Hot Work Permits in Australia for the full process.

Fire watch

A fire watch person stays in the area for at least 30 minutes after welding stops (60 minutes for higher-risk jobs per AS 1674.2) with extinguishers immediately to hand. They're not the welder. They watch for smouldering, and they listen for crackling in walls and ceiling cavities. Most welding-related building fires ignite during the cool-down period after the welder has packed up.

Extinguisher class

The first-response extinguisher for welding fires is a dry chemical powder (ABE) or CO₂. Water is unsuitable around electrical equipment (the welder) and ineffective on running fuel fires. For oxy-fuel work near oils, a foam extinguisher is added. See fire protection equipment.

Specific scenarios that ignite buildings

• Welding above ceiling tiles — sparks drop into the cavity and smoulder in insulation.
• Welding on the outside of a wall — heat conducts through and ignites paper, timber, or insulation on the other side.
• Welding near roof penetrations — bitumen and roofing felt are highly flammable.
• Welding on or near drums and tanks "that used to contain" fuel — vapours remain for weeks. The cleaned-out empty drum has killed more people than the full one.
• Welding in roof spaces where pigeons, possums, or rodents have built nests — dry organic material ignites from a single spark.

Confined-Space Welding

Confined spaces — tanks, vessels, silos, pits, sumps, large pipes, ducts — combine every welding hazard and amplify them. AS 2865 is the Australian Standard for confined space entry; welding inside a confined space requires both an entry permit and a hot work permit, plus specific welding-related controls.

Atmosphere hazards

• Oxygen displacement. Argon and CO₂ shielding gases are heavier than air. They settle in low points of the vessel — sumps, footwells, pits. Argon at 50% concentration is enough to cause unconsciousness within a few breaths and there is no warning sign (no smell, no irritation, just blackout). This is the most common confined-space welder fatality cause.
• Fume accumulation. Welding fume builds rapidly in a sealed volume. Without mechanical extraction, manganese and Cr VI exposures spike to many times WES within minutes.
• Residual contents. Tanks that previously held flammable, toxic, or oxidising materials remain hazardous after draining. A "cleaned" fuel tank that smells fine can still hold enough vapour in the dead pockets to flash on first arc strike.

Controls (per AS 2865 and AS 1674.1)

• Atmosphere test before entry (oxygen 19.5–23.5%, no flammable, no toxic). Re-test during work.
• Mechanical ventilation — supply and exhaust — running continuously during welding. Position exhaust at the lowest point to draw out heavy gases.
• Entry permit and hot work permit. Both.
• Standby person at the entry, never leave. Communication continuous. Retrieval kit (harness and line) on the entrant.
• VRD-equipped welder (Voltage Reduction Device drops OCV between welds — see AS 1674.1).
• Insulating mat under the welder if standing on the vessel floor.
• Shielding gas cylinder remains outside the space, hose passes through. Cylinder valves can be shut from outside in emergency.
• Power tools / lighting on 12 V or 24 V extra-low voltage, or 240 V via RCD with isolation switch outside the space.
• Emergency stop and rescue plan briefed before entry. Rescuers do not enter without their own breathing apparatus — confined-space rescuers are killed more often than the original entrant.

Warning — rescuer fatality. The statistical pattern in confined-space deaths is consistent: the original entrant collapses from oxygen depletion, a co-worker rushes in to help without breathing protection, and is also overcome. Multiple-fatality confined space incidents almost always follow this sequence. Train rescuers separately and equip them with self-contained breathing apparatus.

Compressed Gas Safety

Welding uses high-pressure shielding gas (argon, CO₂, argon/CO₂ mixes, helium) and for oxy-fuel work, oxygen and acetylene or LPG. A full G-size cylinder holds gas at around 200 bar (20 MPa) — enough that a snapped-off valve will launch the cylinder as a missile through a workshop wall.

Storage and handling

• Cylinders stored upright, restrained with chain or strap at two-thirds height.
• Valve guards (caps) on during transport.
• Acetylene cylinders always upright — acetylene is dissolved in acetone inside the cylinder; tipping causes acetone slugs into the regulator.
• Segregate by gas type and fuel-vs-oxidiser. Full and empty separated.
• Cylinder areas ventilated, signed, and protected from impact (bollards near vehicle access).
• Trolley with chain restraint for movement around the workshop. Don't roll cylinders on their edge.

Regulator and hose checks

• Inspect regulators, hoses, and torch fittings before every shift. Cracked rubber, scorched hoses, leaking unions — replace, don't tape.
• Leak-test new connections with soapy water (never a flame). Bubbles = leak.
• Use the correct regulator for the gas. Oxygen regulators must never be used on fuel gas (oil contamination + oxygen = fire).
• Oil and grease anywhere near oxygen fittings will ignite — including hand cream, sunscreen, and lip balm on the operator's hands.

Flashback arrestors

For oxy-fuel work (oxy-acetylene cutting, brazing, heating), flashback arrestors are mandatory at both the regulator outlet and the torch inlet. They contain a flame front travelling backwards from the torch and prevent it reaching the cylinder. A flashback into an acetylene cylinder can rupture the cylinder. AS 4603 is the standard for flashback arrestors. See welding gas regulator guide for full selection detail.

Process-Specific Hazards

MIG / MAG (GMAW)

Highest fume generation of common processes — the wire is continuously consumed and produces dense fume, particularly on solid wire CO₂-shielded work and on flux-cored wire. Contact tip burn-back is common when wire stick-out is wrong; eye injury from molten weld pool spit. Process detail in the MIG welding guide.

TIG (GTAW)

Lower fume than MIG, but ozone generation is higher because of the cleaner, more intense arc UV. High-frequency (HF) arc start can interfere with electronics — pacemakers, hearing aids, sensitive instruments in adjacent rooms. Thoriated tungsten electrodes (red-banded) contain thorium oxide which is radioactive — low risk in normal use but a real risk when grinding electrodes (dust inhalation). Modern alternatives include lanthanated (blue, gold, black) and ceriated (orange) electrodes which are non-radioactive and perform equivalently or better. Process detail in the TIG welding guide.

Stick (SMAW / MMA)

Hot slag splash — the slag layer on the cooling weld bead can pop off violently as it contracts, sending hot fragments at the welder's eyes. Always chip slag with the chipping hammer angled away from the face, and wear safety glasses under the helmet during chipping. Electrode stubs (the unburnt end) are hot — drop them in a metal stub bucket, not on the floor where they catch combustibles.

Flux-cored (FCAW)

High fume and slag — combines the disadvantages of MIG (continuous wire) and stick (slag layer). Particularly hazardous on galvanised or painted parent metal because of the higher heat input. PAPR respirator strongly recommended for sustained FCAW work.

Plasma cutting

Intense UV — shade 8–9 minimum even for low-amperage cutting. High noise (often above 100 dB(A) close to the arc), requires hearing protection. Significant ozone generation. Heavy spatter and dross underneath the cut. See the plasma cutter guide.

Air carbon arc gouging

The highest-noise, highest-fume process commonly used in workshops — sustained currents up to 1,000 A, copper-coated carbon electrodes, compressed air blowing molten metal out of the gouge. Noise routinely exceeds 110 dB(A). PAPR + Class 5 hearing protection + heavy leather + face shield over the helmet — and a clear 10 m exclusion zone for the spray of molten metal.

PPE Selection Summary

Browse AIMS' welding helmets, welding gloves, welding jackets, respiratory protection, eye protection, ear protection, head protection, and the full welding accessories range. Bossweld is AIMS' biggest single welding consumables range (725 products including PPE).

Australian Standards & Codes of Practice

The standards listed below are the ones most often referenced in welding safety audits, insurance claims, and incident investigations. Workplaces should hold copies (or organisational access through SAI Global / Standards Australia) and reference them in their welding safe work method statements (SWMS).

• AS 1674.1 — Safety in welding and allied processes — Electrical. Open-circuit voltage limits, equipment requirements, welding in conductive/wet locations, VRD requirements. [VERIFY: current edition — historically the 1997 edition has been in long use, check Standards Australia for any update]
• AS 1674.2 — Safety in welding and allied processes — Fire precautions. The hot work standard. 10 m exclusion, fire watch duration, permit content, combustible removal/shielding. [VERIFY: current edition]
• AS/NZS 1338.1 — Filters for eye protectors — Filters for protection against radiation generated in welding and allied operations. Specifies the optical performance of welding lens filters, both fixed and auto-darkening. Helmets sold in Australia must carry the AS/NZS 1338.1 mark.
• AS/NZS 1336 — Eye and face protection — Guidelines. General guidance on eye and face PPE selection.
• AS/NZS 1337.1 — Personal eye protection — Eye and face protectors for occupational applications. Safety glasses worn under the helmet and for chipping/grinding.
• AS/NZS 1715 — Selection, use and maintenance of respiratory protective equipment. How to choose the right respirator for the contaminant and exposure level. Required reading for anyone specifying respiratory PPE.
• AS/NZS 1716 — Respiratory protective devices. Performance standard the equipment itself is certified against.
• AS/NZS 1270 — Acoustics — Hearing protectors. Class 1–5 noise reduction rating. Class 5 is the highest, required for gouging and plasma.
• AS/NZS 2210.3 — Personal protective equipment — Safety, protective and occupational footwear. Specification and test methods. The "AS/NZS 2210.3" mark on a boot confirms the safety rating.
• AS/NZS 4602.1 — High visibility safety garments. For welders working in traffic or near mobile plant — note: must be FR-rated.
• AS 2865 — Confined spaces. Entry permit, atmosphere testing, standby person, retrieval, training. The umbrella standard that applies in addition to the welding-specific ones.
• AS 4839 — The safe use of portable and mobile oxy-fuel gas systems for welding, cutting, heating and allied processes. [VERIFY: current edition]
• AS 4603 — Flashback arrestors — Safety devices for use with fuel gases and oxygen or compressed air. The standard for the flashback arrestors fitted to oxy-fuel regulators and torches.
• Safe Work Australia — Welding Processes Code of Practice. The model code (adopted by most Australian jurisdictions with minor variations) that brings the WHS Act requirements together specifically for welding. Covers hazards, controls, training, supervision, PPE, fume management. Free download from Safe Work Australia.
• Safe Work Australia — Workplace Exposure Standards (WES) for Airborne Contaminants. Sets the legally enforceable exposure limits for welding fume, manganese, Cr VI, ozone, and other contaminants. [VERIFY: reference current published values — the 2024 review made significant reductions to several welding-relevant substances.]

AIMS' Note on Welding Safety

This guide is the safety overview — it pulls the major hazards, controls, and standards into one place so welders, supervisors, and procurement teams have a single reference to work from. It's not a substitute for: (1) a properly written Safe Work Method Statement (SWMS) for the specific job; (2) competency-based training in the welding processes used; (3) workplace-specific induction; (4) the current editions of the Australian Standards referenced.

Where this guide flags [VERIFY:] — check the current Safe Work Australia Workplace Exposure Standards schedule and the current editions of AS 1674.1, AS 1674.2, AS 4839, and the model Welding Processes Code of Practice before relying on the figures for compliance or training material. Standards do get updated, exposure limits do get tightened, and your insurer or regulator will reference the current version.

If you're standing up a new welding bay, upgrading an existing one, or responding to a near-miss or incident — engage a competent WHS professional. The investment in proper fume extraction, electrical safety, and training is small compared to a single serious incident or a compliance order.

AIMS supplies the welding PPE, consumables, and equipment that this guide references. If you're not sure what level of respiratory protection your workshop needs, or what helmet to specify for a 350 A MIG operator, ring (02) 9773 0122 between 08:00 and 17:00 Sydney time and Sam Cassar's team can walk through the options. We don't bulk-sell what you don't need — we sell what fits the job.

Frequently Asked Questions

What is arc eye and how long does it last?

Arc eye (photokeratitis) is a UV burn to the cornea from looking at a welding arc without proper eye protection. Symptoms develop 6 to 12 hours after the exposure — a gritty sand-under-the-eyelid feeling, light sensitivity, tearing, and severe pain. It typically resolves within 24 to 48 hours, but cumulative exposures cause permanent corneal damage and contribute to cataract formation later in life. Always wear an appropriately shaded helmet, and use welding screens to protect bystanders within 10 metres of the arc.

What shade welding lens do I need for MIG welding at 200 amps?

For MIG welding in the 160–250 A range, shade 12 is recommended (shade 10 minimum) per AS/NZS 1338.1. Auto-darkening helmets are adjustable across this range. Going one shade darker is uncomfortable but not dangerous; going too light causes arc eye and retinal strain.

Is welding fume really classified as a carcinogen?

Yes. In 2017 the International Agency for Research on Cancer (IARC) reclassified all welding fume as a Group 1 human carcinogen — confirmed to cause lung cancer in humans. Stainless steel fume contains hexavalent chromium (Cr VI), one of the most potent occupational carcinogens. Australian WHS regulators have followed suit by tightening Workplace Exposure Standards for welding-relevant substances. Local exhaust ventilation and P2/P3 respirators are now the expected baseline, not a nice-to-have.

What's the difference between P2 and P3 respirators for welding?

P2 filters out 94% of fine particles and is adequate for occasional mild-steel welding in well-ventilated areas. P3 filters out 99.95% and is required for stainless steel, galvanised steel, painted or coated parent metal, and full-shift welding exposure. P3 typically requires a reusable half-face or full-face respirator, or a powered air-purifying respirator (PAPR) integrated into the welding helmet. See the respirator guide for full selection.

Why is welding galvanised steel dangerous?

The zinc coating vapourises in the arc and forms zinc oxide fume, which causes "metal fume fever" — a flu-like illness with fever, sweats, headache, and joint pain that develops 4 to 12 hours after exposure and lasts about 24 hours. It's not usually permanently harmful but it's deeply unpleasant. Repeated exposures may cause tolerance ("monday morning fever" — symptoms after the weekend break). Control with local exhaust, a P3 respirator, and where possible grind off the galv coating in the immediate weld zone before welding.

Can I weld on a tank that used to hold fuel?

Not without thorough purging, atmosphere testing, and a hot work permit. Vapours from previous fuel contents remain in the tank for weeks after draining and even in apparently empty cleaned tanks. Confirmed-empty tanks have killed welders. Standard practice: drain, vent, steam-clean or detergent-wash, fill with water or inert with nitrogen / argon to displace any residual vapour, atmosphere test for LEL (lower explosive limit), and only then permit welding. AS 2865 confined space rules also apply because the tank is itself a confined space.

What is the 10 metre rule in welding?

AS 1674.2 (and the international equivalent NFPA 51B) requires that combustible materials within 10 m (35 ft) of the welding location be removed or shielded with non-combustible covers before hot work begins. The 10 m radius is the typical spark travel distance from common welding operations — sparks from elevated work travel further. The rule applies in all directions including below the work and behind walls where heat may conduct through.

Do I need a hot work permit to weld in my own workshop?

Inside a designated welding bay with fire-rated construction, non-combustible flooring, and engineered ventilation — no permit needed because the controls are already engineered into the space. Outside that designated bay — anywhere else on the premises, including the loading dock, the storage area, or anywhere with combustible materials nearby — a hot work permit is required by AS 1674.2 and most workplace insurance policies. The permit isn't bureaucracy — it forces the team to think about fire watch, extinguisher placement, and combustible removal before starting.

How long does the fire watch need to stay after welding?

AS 1674.2 specifies a minimum 30-minute fire watch after welding stops, extended to 60 minutes for higher-risk situations (welding near concealed combustibles, in roof spaces, near insulation). Most welding-related fires ignite during the cool-down period, not during welding — particularly fires that smoulder in concealed cavities and break out hours later. Fire watch isn't optional and isn't done by the welder.

What's the safest way to weld inside a tank or pressure vessel?

Confined-space welding combines every welding hazard. The non-negotiable controls are: (1) confined space entry permit under AS 2865, (2) hot work permit under AS 1674.2, (3) atmosphere test before entry and continuously during work — oxygen 19.5 to 23.5%, no flammable, no toxic, (4) mechanical ventilation with exhaust at the lowest point to draw out heavy gases like argon and CO₂, (5) standby person at the entry with retrieval kit and emergency communication, (6) Voltage Reduction Device (VRD) on the welder per AS 1674.1, (7) insulating mat under the welder, (8) shielding gas cylinder remains outside the vessel. Rescuers must wear self-contained breathing apparatus — most confined-space deaths happen when someone rushes in to help without protection.

Can the welding earth (work) clamp go anywhere on the structure?

No. The work clamp must go onto the actual workpiece, or onto a clean bare-metal point of the bench it's clamped to. Putting the work clamp on pipework, structural steel, or other equipment causes the welding current to travel through those items to find earth — burning through bearings, control cables, electrical wiring in walls, and sometimes setting fire to insulation. The path between the work clamp and the arc should be as short and as direct as practicable.

Do I really need a flashback arrestor on oxy-acetylene gear?

Yes — at both the regulator outlet and the torch inlet. AS 4603 specifies flashback arrestors for fuel gas / oxygen systems, and AS 4839 (oxy-fuel safe use) requires them on portable equipment. A flashback is when the flame front travels back up the hose toward the regulator and cylinder; without arrestors, a flashback can reach an acetylene cylinder and cause the cylinder to rupture catastrophically. Flashback arrestors are inexpensive and they save the workshop.

Why are some TIG tungstens marked as radioactive?

Thoriated tungsten electrodes (red-banded, 2% thorium oxide) have been the standard DC TIG electrode for decades. Thorium oxide is mildly radioactive — the risk in normal welding is negligible, but grinding the electrode produces a fine dust that should not be inhaled. Modern alternatives — lanthanated (gold, blue, black banded — 1.5%, 2%, 2% lanthanum oxide), ceriated (orange — 2% cerium oxide) — are non-radioactive and perform equivalently or better across most applications. If you're still buying thoriated electrodes by habit, consider the switch.

What clothing should welders avoid wearing under their welding jacket?

Synthetic fabrics — polyester, nylon, fleece, polypropylene thermals — must not be worn next to the skin while welding. When a spark lands on synthetic fabric it melts and fuses to the skin, turning a routine minor burn into a deep skin-graft case. Wear cotton or wool base layers, cotton or FR-cotton coveralls, and leather over the top. This includes hi-vis vests — standard polyester hi-vis melts and must be replaced with FR-rated hi-vis garments per AS/NZS 4602.1 for welders working near traffic or mobile plant.

What's the legal exposure limit for welding fume in Australia?

The Safe Work Australia Workplace Exposure Standard (WES) for welding fume (not otherwise classified) is 1 mg/m³ as an 8-hour time-weighted average. Specific components have lower limits: manganese is 0.02 mg/m³ respirable (a 50× reduction from the historical 1 mg/m³ standard), hexavalent chromium is around 0.05 mg/m³ [VERIFY: current schedule may be lower], ozone is 0.1 ppm. These limits are legally enforceable under WHS regulations. Routine MIG welding on mild steel without local exhaust ventilation will breach the manganese limit. If welders are exposed at or near these limits, exposure monitoring and health surveillance are required.

Is auto-darkening better than a fixed-shade welding helmet?

For most welders, yes — auto-darkening helmets stay light enough to see the joint when setting up, dark when the arc strikes, and back to light when it stops. Fixed-shade is fine for production single-process work where the welder doesn't lift the helmet between welds. Buy an AS/NZS 1338.1-marked helmet from a reputable supplier — counterfeit helmets with apparently dark filters that fail the UV/IR transmission test are a known problem on the cheap end of the market. See the welding helmet guide for full selection criteria including viewing area, optical clarity rating (1/1/1/1 is best), grind mode, and PAPR integration.

What training do welders need under Australian WHS law?

Welding is a "high-risk" task under most jurisdictions' WHS regulations, but not every welding job requires a formal certificate. The expectations are: (1) competency-based training in the specific welding processes used (typically through TAFE certificates such as MEM05 or industry-specific Cert II/III courses); (2) site induction including the workplace's SWMS and emergency procedures; (3) hot work permit training where permits are used; (4) confined space entry training (separate certification) for any confined-space welding work; (5) refresher training on a periodic basis. The Safe Work Australia Welding Processes Code of Practice sets out the model expectations — check your state regulator for the specific requirements.

What should I do if I get arc eye?

Cool the eyes (closed cold compress, not direct ice), darken the room, take paracetamol or ibuprofen for the pain, and rest. Don't rub the eyes. The corneal surface heals within 24 to 48 hours in most cases. If pain persists beyond 48 hours, if vision is affected, or if there's discharge, see a doctor — possible secondary infection or deeper injury. For severe cases, the GP or hospital may prescribe topical anaesthetic drops, but these aren't a long-term solution — they delay healing. The real answer is to prevent the next one with proper helmet use and bystander screens.