HSE RR683 – Effective Control of Gas Shielded Arc Welding Fume
This HSE Research Report examines whether Local Exhaust Ventilation (LEV) can effectively control exposure to gas-shielded arc welding fume without compromising weld quality.
The research was commissioned after inspectors found that LEV systems were often left unused because welders believed extraction airflow would remove shielding gas and introduce weld defects. HSE therefore undertook a structured research programme to determine whether effective fume capture and acceptable weld integrity could be achieved simultaneously.
The project investigated:
- Capture efficiency of different LEV hood designs
- Hood positioning and extraction effectiveness
- Airflow effects on shielding gas performance
- Weld integrity and porosity
- Cross-draught effects
- On-gun extraction systems
- Practical welding positions and configurations
The report concludes that satisfactory welding fume extraction can be achieved using properly designed LEV systems without compromising weld integrity when standard welding parameters are used.
This resource is relevant to:
- LEV Designers
- LEV Installers
- Welding Engineers
- Commissioning Engineers
- P601 Thorough Examination & Test Engineers
- Occupational Hygienists
- Health & Safety Professionals
- Fabrication Managers
- Process Engineers
- Duty Holders
Source Document
View the HSE guidance here:
Source: Health and Safety Executive (HSE)
Document Type: Research Report (RR683)
Status: Current
Last reviewed by LEVCentral: June 2026
LEVCentral Expert Commentary
RR683 remains one of the most valuable pieces of evidence available to LEV designers working with welding processes because it directly challenges a long-standing misconception within industry.
Historically, many welders resisted the use of LEV on the grounds that extraction airflow would remove shielding gas and create porosity within the weld. HSE’s research programme was specifically designed to investigate whether these concerns were technically justified. The results demonstrated that effective fume capture can be achieved while maintaining weld integrity when extraction systems are correctly designed and positioned.
For LEV professionals, the report reinforces several important principles:
- Hood design is critical to capture performance.
- Hood positioning often has a greater influence than extraction volume alone.
- Excessive cross-draughts can affect welding operations.
- Properly engineered extraction systems can achieve both exposure control and process quality.
- On-gun extraction systems can provide effective control in certain applications.
- Extraction effectiveness should always be verified through commissioning and performance testing.
The report is particularly useful when discussing welding-fume controls with fabricators, welding supervisors and production managers because it provides independent evidence supporting LEV implementation.
Since the publication of RR683, the importance of welding-fume control has increased significantly. HSE’s 2019 enforcement changes recognised all welding fume, including mild steel welding fume, as a carcinogenic exposure requiring effective engineering controls. LEV is now expected for virtually all indoor welding operations and suitable controls are required even when welding outdoors.
From an LEVCentral perspective, RR683 should be viewed as a foundational document demonstrating that exposure control and production quality are not competing objectives. Well-designed LEV systems can achieve both.
Further Resources
- HSG258 – Controlling Airborne Contaminants at Work (LEV)
- INDG409 – Time to Clear the Air! A Workers’ Pocket Guide to LEV
- HSE Welding Resources Portal
- COSHH Essentials for Welding, Cutting and Allied Tasks
- RR770 – Exposure to Stainless Steel Welding Fume
- HSE Safety Alert – Welding Fume Enforcement Changes
Recommended Learning
- P602 LEV Design Principles
- P600 Methods for Testing Effectiveness of LEV
- P601 Thorough Examination & Testing of LEV Systems
- P604 LEV Performance Evaluation and Management
