In April 2021, Japan amended the Ordinance on Prevention of Hazards due to Specified Chemical Substances to add welding fumes to the list of controlled substances. The amendment introduced new requirements for local exhaust ventilation, respiratory protection, and health monitoring for welders. For welding workshops and contractors, the practical implications are significant.
What the 2021 amendment requires ¶
The amendment requires employers to implement local exhaust ventilation (LEV) or equivalent fume control measures at welding workstations. Where LEV is not practicable. For example, on outdoor site work or in confined spaces. Respiratory protective equipment (RPE) must be provided and its use enforced. Employers must also conduct health monitoring for welders exposed to welding fumes, including periodic lung function checks, and keep records of the monitoring results.
Local exhaust ventilation in practice ¶
For a fixed workshop, LEV means a capture hood positioned close to the welding arc, connected to a duct and filtration unit that removes fume particles before exhausting air outside the building. The system must be designed to achieve a capture velocity sufficient to draw fume away from the welder's breathing zone. In our Kawasaki workshop, the LEV system in the TIG bay was designed by an industrial hygiene consultant and tested after installation to confirm capture velocity. The test records are kept on file for inspection.
Site work and respiratory protection ¶
On construction sites and plant shutdowns, fixed LEV is rarely practicable. The amendment requires that welders on site work use RPE rated to at least P3 for particulate fume, or a powered air-purifying respirator (PAPR) where the work is sustained. We issue appropriate RPE to all site welders and include RPE requirements in our site-specific risk assessments. Clients who require evidence of our fume control arrangements can request a copy of our risk assessment before work begins.
If you are a plant operator or construction contractor and need to confirm that your welding contractor with the 2021 fume control requirements, we can provide documentation of our LEV system, RPE provision, and health monitoring programme on request.