Health, Safety and Environmental Protection
Domain 7: Health, safety and environmental protection
This domain tests hazard recognition and control in welding operations. The exam expects specific controls, not slogans: fume extraction, radiation protection, electrical safety, fire prevention and confined-space procedure.
Principal hazards
Welding fume contains metal oxides and process-dependent gases; local exhaust ventilation at the arc is the primary control, supported by general ventilation and respiratory protection where needed. Arc radiation causes arc eye and skin burn; screens must meet the relevant transmittance requirements, such as EN ISO 25980, and nearby workers need protection. Electric shock risk rises with wet conditions, damaged cables and secondary voltage; the welding return must be close to the work. Fire and explosion risks require a hot-work permit, removal of combustibles and fire watch. Confined spaces need gas testing, isolation, ventilation, an attendant and rescue arrangements.
Environmental controls
Waste, spent flux, slag, fume filters and packaging need controlled disposal. Noise from plasma cutting and grinding may require hearing protection and assessment.
Worked example
A welder must repair the inside of a tank that previously held solvent. The correct sequence is isolation and cleaning, gas testing before entry and during work, forced ventilation, local extraction at the arc, an attendant outside, a rescue plan and a permit. Starting work after a single test at the manhole is inadequate because solvent vapour can migrate or be released by heat.
Traps
Relying on general ventilation instead of extraction at the arc. Assuming a welding helmet protects others. Treating a confined space as safe once it has been ventilated. Forgetting the fire watch after hot work ends.