Welding safety
Personal protection, fume extraction, hot work, electrical safety, first aid.
Four hazards, and each has a standard behind it: eyes and skin from radiation and spatter, lungs from fume, the building from fire, and the welder from electric shock.
Two of them are underestimated in a specific way. Fume was reclassified as a Group 1 carcinogen in 2017 — all welding fume, not only the stainless fraction — and the control that works is extraction at the arc, not an open door. Electric shock is dismissed because welding voltage is low, but the voltage that matters is the open-circuit voltage before the arc strikes, and the danger threshold falls sharply on wet skin.
The third, fire, is mostly about time: most hot work fires begin an hour or more after everyone has left.
- Personal protective equipment Helmet EN 175/379 and shade by current, EN 12477 type A/B gloves, EN ISO 11611 class 1/2 clothing, WG boots: PPE for MMA, MIG/MAG, TIG, cutting, overhead.
- Welding fume and ventilation How much fume MAG, TIG and flux-cored welding make (mg/s, grams per shift), the exposure limits, how close the fume extractor must be and how to ventilate a shop.
- Gloves and clothing Class 2 means 25 drops instead of 15 and 16 s instead of 7: EN ISO 11611 classes and A1/A2, how 11612 differs, EN 12477 A/B gloves, washing and retirement.
- Respiratory protection Which respiratory PPE a welder needs: FFP2 or FFP3, when a powered hood (PAPR) is required, protection factors, filter changes and the common fit mistakes.
- Stainless fume: chromium VI Why stainless fume is carcinogenic, which process produces the most of it, and what limit for chromium VI applies across the European Union.
- Hot work and fire safety Why sparks start fires hours later, what a hot work permit covers, and how to leave a site with nothing left smouldering.
- Electrical safety in welding Open-circuit voltage of 50–90 V, the 113 V DC and 48 V AC limits for S-marked work, why a 30 mA RCD will not stop a shock from the holder, and VRD.
Frequently asked questions
Is welding fume really carcinogenic?
Yes — the IARC reclassified all welding fume as a Group 1 carcinogen in 2017, not only the stainless-steel fraction. That is why extraction requirements tightened across Europe afterwards, and why an open door does not count as a control.
Welding voltage is low. Is electric shock a real risk?
Yes. The figure that matters is the open-circuit voltage before the arc strikes — 50 to 90 V, up to 113 V on some AC machines — and the danger threshold is around 50 V. Wet skin drops the body's resistance by an order of magnitude.
How long does a fire watch have to stay?
At least an hour after the work finishes, and two under some regimes. Most hot work fires start after everyone has left, from a spark that smouldered in dust or insulation.