Welding Fume Exposure Monitoring – Sysco Environmental Ltd Case Study
Learn how Sysco Environmental Ltd helped a UK steel fabrication facility assess and control exposure to hazardous welding fumes. Discover health risks, metal-specific effects, and practical control measures to ensure COSHH compliance.
How a Fabrication Site Controlled Welding Fume Exposure to Stay Well Below Safety Limits
Sysco Environmental Ltd conducted a workplace exposure assessment at a steel fabrication site in Cambridgeshire. In addition to paint-related hazards, the evaluation focused on welding fume exposure, especially during MIG and TIG welding operations on carbon steel and stainless steel components.
Personal air sampling was carried out on employees undertaking welding tasks in a large open-sided workshop. The primary goal was to evaluate the concentration of airborne metal particulates and determine if current control measures adequately protected workers from hazardous exposure.
Understanding Welding Fumes and Metal Additives
Why Metals Are Added to Steel
Steel alloys are formulated by introducing specific metals to enhance mechanical, thermal, and corrosion-resistant properties:
Chromium improves hardness and corrosion resistance (main element in stainless steel).
Nickel adds strength, toughness, and oxidation resistance.
Manganese improves workability and hardness.
Iron serves as the base metal but contributes to fume density during welding.
Zinc, though not added directly, may be present from galvanised coatings and poses significant respiratory hazards when vaporised.
These metals become airborne as ultrafine particles and fumes during welding, creating a complex mix of potentially hazardous substances.
Health Effects of Common Welding Fume Metals
| Metal | Purpose in Alloy | Primary Health Effect |
|---|---|---|
| Iron | Base material | Benign pneumoconiosis (siderosis), respiratory irritation |
| Manganese | Improves strength and hardness | Neurological effects (manganism – similar to Parkinson’s) |
| Chromium | Corrosion resistance (stainless steel) | Chromium VI: Carcinogenic, lung and nasal cancer risks |
| Nickel | Corrosion resistance, strength, oxidation stability | Respiratory sensitiser, lung cancer risk |
| Zinc | Found in galvanised coatings | Causes metal fume fever (flu-like symptoms) |
Welding fumes are now classified as carcinogenic to humans by the International Agency for Research on Cancer (IARC). Prolonged exposure may lead to chronic respiratory diseases and increased cancer risk.
Monitoring Methodology
Welding fume exposure monitoring was conducted in line with HSE guidance and MDHS 14/4. Personal samplers were worn by welders throughout their shift to evaluate time-weighted average exposure to inhalable metal particulates.
Key Sampling Parameters:
Task: MIG/TIG welding of mild and stainless steel
Sampling Time: 8-hour shift
Equipment: IOM samplers with gravimetric analysis and ICP-OES for metal composition
Metals Analysed: Iron, Chromium, Manganese, Nickel, Zinc
Monitoring Results
| Substance | Exposure Level (mg/m³) | Workplace Exposure Limit (WEL) | Interpretation |
|---|---|---|---|
| Inhalable Dust | <0.11 mg/m³ | 10 mg/m³ | Negligible; less than 1.1% of WEL |
| Iron | <0.11 mg/m³ (as dust) | 5 mg/m³ (respirable) | Within safe limits |
| Manganese | <0.01 mg/m³ | 0.2 mg/m³ (inhalable) | Very low; less than 5% of WEL |
| Chromium | <0.004 mg/m³ | 0.5 mg/m³ (Cr III); 0.05 mg/m³ (Cr VI) | Well below WEL; not Cr VI-specific |
| Nickel | <0.003 mg/m³ | 0.1 mg/m³ | Low exposure |
| Zinc | <0.01 mg/m³ | 5 mg/m³ | Negligible |
Conclusion: Welding fume exposure levels were well below occupational limits. However, continued vigilance is necessary due to the carcinogenic classification of some metals, particularly Nickel and Chromium VI.
Recommendations for Exposure Control
1. Local Exhaust Ventilation (LEV)
Status: No fixed LEV system observed.
Recommendation: Install or upgrade LEV (e.g. portable fume extraction units with hoods) to capture fumes at source and minimise spread in open workshops.
2. Respiratory Protective Equipment (RPE)
Status: Disposable RPE used inconsistently.
Recommendation: Introduce mandatory use of FFP3 masks or powered air-purifying respirators (PAPR) for prolonged welding. Provide face-fit testing and regular filter replacement schedules.
3. Health Surveillance
Status: Not currently in place.
Recommendation: Implement annual respiratory health checks for welders, particularly those working with stainless steel and galvanised components.
4. Training
Status: Basic awareness provided.
Recommendation: Deliver regular training on:
Specific health risks of metals in welding fumes
Proper RPE use and maintenance
Recognising early symptoms of respiratory illness
Conclusion
Sysco Environmental Ltd’s assessment confirmed that welding fume exposure at the Cambridgeshire fabrication site was within safe limits, but identified opportunities for proactive improvement. Given the toxic and carcinogenic nature of key metals in welding fumes, a precautionary approach is vital.
By reinforcing ventilation, enforcing consistent RPE use, and training staff on fume hazards, the facility can continue to protect workers and meet COSHH obligations.
OUR EXPERT
Tomas Gabor
0800 433 7914
Sysco Environmental Ltd are specialists in welding fume exposure assessment. We provide detailed air sampling, metal-specific analysis, LEV design reviews, and RPE protocols to help businesses manage risks from toxic metals like chromium, nickel, and manganese—ensuring full compliance with COSHH regulations and protection of long-term respiratory health.