Welding Safe Work Method Statement

Welding processes generate complex fumes containing metal oxides, gases, and particulates that pose serious respiratory hazards through both acute and chronic exposure. The fume composition varies with welding process, base metal, coatings, and filler materials, but typically includes iron oxide, manganese, chromium, nickel, zinc, copper, and other toxic metals. Particle sizes range from visible smoke to sub-micron particles that penetrate deep into lungs and cannot be expelled by natural clearance mechanisms. Acute exposure causes metal fume fever with flu-like symptoms including fever, chills, muscle aches, and nausea, typically occurring 4-8 hours after exposure and resolving within 24-48 hours. Chronic exposure leads to pneumoconiosis (welder's lung) with progressive lung scarring reducing respiratory capacity, chronic bronchitis, and asthma. Welding fume is classified as Group 1 carcinogen causing lung cancer with sufficient evidence from multiple epidemiological studies. Stainless steel welding generates hexavalent chromium, an extremely toxic compound causing lung cancer, nasal perforation, and allergic sensitisation. Manganese fume causes Parkinsonism with tremors, balance problems, and neurological deterioration. Confined space welding without adequate ventilation creates immediate life-threatening fume concentrations. Galvanised steel welding produces zinc oxide fumes causing severe metal fume fever. Coatings including paints, oils, and surface treatments generate additional toxic fumes during welding.

Consequence: Pneumoconiosis causing progressive respiratory failure and death, lung cancer from chronic fume exposure, Parkinsonism from manganese poisoning, metal fume fever requiring hospitalisation, occupational asthma ending welding careers, and chronic bronchitis causing lifelong breathing difficulties.

Welding and cutting operations generate intense heat, showers of sparks, and molten metal droplets that ignite combustible materials causing fires and explosions. Welding sparks reach temperatures of 1500-2000°C and travel horizontally up to 10 metres from welding point, easily igniting paper, cardboard, timber, flammable liquids, and accumulated dust. Sparks fall through gaps in floors, grating, and penetrations, igniting materials on lower levels outside welder's view. Radiant heat from welding arc ignites combustible materials up to 1 metre away without direct spark contact. Welding on or near fuel tanks, drums, or vessels previously containing flammable liquids causes catastrophic explosions if containers have not been properly purged, cleaned, and certified gas-free by qualified persons. Even 'empty' containers retain vapours at explosive concentrations. Cutting operations produce more sparks and molten metal than welding, creating higher ignition risk. Hot work near stored flammable liquids, gases, or chemicals ignites vapours. Dust accumulations including sawdust, grain dust, or combustible powders are easily ignited by welding sparks. Fires developing slowly may go undetected during welding, then spread extensively before discovery. Structural steel members conduct heat, igniting materials in contact with steel far from welding location.

Consequence: Major construction site fires destroying buildings and materials, explosions causing multiple fatalities and serious burn injuries, severe burn injuries from flash fires, project shutdown and massive financial losses, and fatalities to welders and nearby workers from explosions in vessels or confined spaces.

Arc welding equipment operates at dangerous voltages creating electrocution hazards through primary circuit (mains input power at 240-480 volts) and secondary circuit (welding output at 20-80 volts). Primary circuit electric shock occurs from damaged input cables, faulty connections, or contact with unprotected terminal connections, causing immediate fatal electrocution similar to household electrical hazards. Secondary circuit voltage, whilst lower, is still lethal in wet conditions or confined spaces with large conductive surfaces. Welders working in wet conditions, in metal vessels, or whilst perspiring provide low-resistance paths for current flow increasing electric shock risk. Damaged electrode holders, broken welding cables, or contact with earth through damp clothing whilst holding electrode creates shock paths through body. Working inside tanks, vessels, or excavations with welders in contact with conductive surfaces dramatically increases electrocution risk as entire body can become part of electrical circuit. Using welding equipment without residual current device (RCD) protection eliminates automatic disconnection during fault conditions. Repairing or modifying welding equipment whilst powered creates primary voltage shock hazards. Multi-welder operations increase shock risk from contact with other welders' equipment or earth connections.

Consequence: Fatal electrocution from primary voltage shock through damaged cables or connections, cardiac arrest from secondary voltage shock in wet or confined conditions, severe electrical burns requiring extensive treatment, neurological damage from electric shock affecting motor control, and drowning if electric shock occurs during confined space welding in presence of water.

Welding arcs emit intense ultraviolet (UV) and infrared (IR) radiation that causes serious eye injuries and skin damage through direct exposure or reflection. Ultraviolet radiation causes photokeratitis (arc eye or welder's flash), an extremely painful condition where UV radiation burns the cornea causing sensation of sand in eyes, severe light sensitivity, tearing, and temporary vision impairment developing 3-12 hours after exposure. Repeated arc eye episodes can cause permanent corneal scarring affecting vision. Prolonged UV exposure without protection causes cataracts requiring surgical treatment. Direct viewing of welding arc even momentarily causes retinal burns and permanent vision damage. Infrared radiation causes retinal damage accumulating over time potentially leading to vision loss. UV and IR radiation reflect from light-coloured walls, ceilings, and polished metal surfaces, affecting workers not directly viewing arc. Skin exposure to arc radiation causes painful burns similar to severe sunburn, with repeated exposure increasing skin cancer risk. Face and neck areas not protected by welding helmets receive radiation exposure. Helpers and nearby workers not wearing appropriate eye protection suffer arc eye from reflected radiation. Inadequate welding curtains or screens allow radiation to escape welding area affecting bystanders.

Consequence: Photokeratitis (arc eye) causing severe pain and temporary blindness, permanent vision loss from retinal damage, cataracts requiring surgery and affecting long-term vision, skin burns requiring medical treatment, increased skin cancer risk from chronic UV exposure, and permanent eye damage to helpers and bystanders not wearing appropriate protection.

Oxy-acetylene welding and shielding gas systems for MIG/TIG welding use high-pressure gas cylinders containing compressed oxygen, acetylene, argon, or CO2 at pressures up to 15,000 kPa (2200 psi). Cylinder damage from dropping, impacts, or exposure to heat can cause catastrophic failure releasing stored energy equivalent to explosive detonation. Acetylene is extremely unstable and decomposes explosively if cylinders are stored horizontally allowing acetone solvent to enter valve, or if pressure exceeds safe limits. Oxygen dramatically accelerates combustion, with even normally non-flammable materials burning vigorously in oxygen-enriched atmospheres. Oxygen leaks onto clothing or oily surfaces create fire hazards where garments or materials ignite explosively. Acetylene leaks form explosive mixtures with air, igniting from any spark or heat source. Flashback occurs when flame burns back into torch, hoses, or regulators, potentially causing explosions. Cylinders without proper securing fall over, breaking valves and becoming missiles from thrust of escaping gas. Incompatible regulators or using oil on oxygen fittings causes fires. Argon and CO2 shielding gases displace oxygen in confined spaces causing asphyxiation without warning as these gases are colourless and odourless.

Consequence: Cylinder explosion causing multiple fatalities and destroying buildings, severe burns from oxygen-enriched fire, explosions from acetylene ignition killing welders and nearby workers, asphyxiation from inert gas displacement in confined spaces, and catastrophic failure from cylinder damage launching cylinder as uncontrolled missile.

Welding operations frequently require awkward working positions including overhead welding, confined space work, kneeling for extended periods, and twisting to access difficult joints. Maintaining uncomfortable postures whilst performing detailed work causes musculoskeletal injuries affecting back, shoulders, neck, and knees. Overhead welding requires holding heavy welding guns or electrode holders above shoulder height for extended periods causing shoulder strain and neck injuries. Welding in confined spaces requires working in cramped positions, often lying on sides or backs to access joints. Manual handling of gas cylinders, welding machines, and steel components causes back injuries. Welders often work in fixed positions determined by workpiece location rather than ergonomically optimal postures. Repetitive welding operations cause cumulative trauma disorders. Thick protective clothing and welding helmets restrict movement and add weight to postural loading. Ground-level welding requires prolonged kneeling or squatting. Fatigue from uncomfortable positions reduces attention and increases error risk.

Consequence: Chronic back pain from awkward postures and heavy manual handling, shoulder injuries from overhead welding causing rotator cuff damage, knee injuries and arthritis from prolonged kneeling, neck strain from looking upward or to sides during welding, and cumulative trauma disorders affecting hands and wrists from repetitive movements.