Welding creates strong metal joints, but it also produces fumes and gases that can seriously harm your health. Unlike burns or eye injuries, the effects of welding fumes often don’t show up right away, which makes them easy to underestimate.
What Are Welding Fumes?
When metal is heated above its boiling point, it vaporizes. As this vapor cools, it turns into tiny solid particles called welding fumes. These particles mainly come from:
The base metal being welded, the electrode or filler metal, fluxes, coatings, paints, oils, and residues.
The visible fume cloud often contains metals, metal oxides, silicates, and fluorides.
Health Effects of Welding Fume
Short-term exposure can cause: Nausea, dizziness, headaches, Irritation of the eyes, nose, and throat, Metal fume fever (flu-like symptoms)
Long-term or repeated exposure can lead to: Lung cancer, larynx cancer, urinary tract cancer, Chronic lung problems, Nervous system and kidney damage.
Some specific hazards include:
- Beryllium, cadmium, chromium, nickel, manganese – Can cause cancer, lung damage, neurological issues, and skin problems.
- Iron oxides – Can cause siderosis (iron deposits in the lungs).
- Hexavalent chromium (from stainless and chromium steels) – A known human carcinogen; very toxic to eyes, skin, nose, throat, and lungs.
Welding can also generate dangerous gases, such as:
- Carbon monoxide – Headaches, dizziness, unconsciousness, death at high levels
- Ozone, nitrogen oxides, hydrogen fluoride, phosgene – Serious lung and respiratory damage
- Argon, CO₂, helium – Can displace oxygen and cause suffocation in confined or poorly ventilated areas.
How to Reduce Exposure
- Know the hazards
- Read and follow Safety Data Sheets (SDS) and manufacturer’s instructions for base metals, electrodes, and coatings.
- Understand what you’re welding and what it can produce when heated.
- Use ventilation and fume extraction
- Use local exhaust ventilation (LEV) or fume extraction at the arc to pull fumes away from your breathing zone.
- Make sure the work area has good general ventilation to prevent buildup of fumes, gases, and oxygen displacement.
- Aim exhaust away from other workers and, when possible, vent outdoors.
- Choose safer options when possible
- Look for consumables and processes that generate less fumes or contain fewer toxic metals.
- When practical, select welding methods that naturally produce lower fume levels.
- Work practices
- Keep your head out of the fume plume—position yourself so fumes move away from your face.
- Avoid welding in confined spaces without proper ventilation, permits, and monitoring.
- Take breaks in cleaner air to reduce overall exposure.
- Clean the metal first
- Remove paints, primers, oils, rust inhibitors, and other coatings whenever possible.
- The cleaner the surface, the less toxic the fumes.
- Respiratory protection
- Use appropriate respirators when ventilation alone cannot keep exposure within safe limits.
- Remember: respirators do not replace engineering controls and ventilation; they are a backup, not the primary solution.
