Welding, cutting, and brazing

You need a fire watch when welding, cutting, or brazing operations are done where sparks, hot slag, or heat could cause fires or explosions and when it’s not possible to fully protect combustibles—this means assigning someone to watch for and quickly put out fires. Employers must plan for fire prevention and protection during hot work and provide a fire watch when operations present a fire hazard, especially in locations with combustibles or confined spaces.

• A fire watch should be trained, equipped with extinguishers, and remain in place during the work and for a suitable time after completion to watch for smoldering fires.
• Remove or protect combustible materials when practical; if they can’t be moved, a fire watch is required.

See 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for the regulatory requirements and employer responsibilities.

You must wear an appropriate filter plate and a welding helmet or hood with the correct shade to protect your eyes and face from the intense light and sparks produced during arc welding. The employer must provide and ensure the use of eye and face protection suitable for the specific welding process and intensity.

• Use the correct shade number for arc welding to prevent flash burns; lighter shades are for grinding or torch cutting, darker shades for higher current arc welding.
• In addition to a helmet, wear safety goggles or a face shield when grinding, chipping, or when flying particles are present.

Refer to the protective equipment and eye-protection requirements in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) to select proper filters and shields.

Local exhaust ventilation is required whenever welding processes generate airborne contaminants (fumes, gases, or particulates) that cannot be controlled by general ventilation or when worker exposure could exceed safe levels. Employers must provide ventilation or respiratory protection to keep exposures below recognized limits.

• Use localized fume extraction (hoods or arms) near the weld area to capture contaminants at the source.
• If ventilation alone cannot control exposures, use appropriate respirators and follow a respiratory protection program.

See 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for requirements on ventilation and controlling welding fumes.

You must identify coatings and take precautions because burning or heating coatings (paint, galvanizing, or plastics) can release toxic fumes that require ventilation or respiratory protection. Employers should remove coatings when practical, use ventilation, or provide respirators to protect workers from harmful vapors.

• Remove paint or coatings mechanically before welding if feasible; if not, use local exhaust ventilation and appropriate respirators.
• Be aware of specific toxic coatings (e.g., lead paint, chromates, cadmium) and follow more stringent controls or medical surveillance as needed.

Consult 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for ventilation and fume control expectations during welding on coated surfaces.

Compressed gas cylinders must be stored upright, secured to prevent tipping, and kept away from heat sources and combustible materials. Cylinders should be capped when not in use, valves closed, and stored in a well-ventilated area.

• Store oxygen cylinders at least 20 feet from fuel-gas cylinders (e.g., acetylene) or separate them with a noncombustible barrier at least 5 feet high with a fire resistance rating of at least 30 minutes.
• Keep cylinders away from sparks, open flames, and electrical equipment; use cylinder carts or chains to secure them during use and storage.
• Never allow oil or grease on oxygen cylinder valves or regulators.

Refer to safe handling and storage guidance in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for specific requirements.

You must use the correct regulators, pressure-reducing devices, flashback arrestors where required, and properly matched fittings and hoses; connections should be tight, leak-checked, and free of oil or grease. Regularly inspect hoses and replacements must be rated for the gas and pressure.

• Use flashback arrestors on fuel gas and oxygen lines to prevent flame from traveling back into the system.
• Check for leaks with a soapy-water solution—never use a flame for leak testing.
• Replace hoses that are cut, abraded, or show signs of deterioration; keep hoses routed to avoid kinks and damage.

See 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for regulator, hose, and connection safety requirements.

You must wear respiratory protection when ventilation and other engineering controls cannot keep airborne welding contaminants below permissible limits. Employers are required to evaluate exposures and provide respirators and a respiratory program when necessary.

• Use cartridge respirators for lower-level exposures and powered air-purifying or supplied-air respirators for higher exposures or when contaminants are unknown.
• Ensure fit testing, medical evaluation, and training are provided as part of a written respiratory protection program.

For employer obligations on controlling exposures and using respirators, see 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) and applicable respiratory protection standards.

You must treat closed containers as hazardous until they are tested, cleaned, and proven safe; never weld or cut on a container that has held flammable, toxic, or reactive substances without proper cleaning and atmospheric testing. Employers must ensure containers are purged, ventilated, and tested before hot work.

• Remove or neutralize residues, ventilate the container thoroughly, and test the atmosphere for flammability and toxic gases before entering or performing hot work.
• Use a qualified person to clear inflammable vapors and establish a safe procedure; maintain a fire watch during and after the work.

Refer to safe practices for hot work on containers and tanks in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing).

You must protect bystanders by using welding screens or curtains, redirecting sparks, and clearly marking welding areas to prevent exposure to bright arc light, flying sparks, and fumes. Employers should set up physical barriers and control access to hot work areas.

• Use nonflammable welding curtains or screens to block arc flash from nearby workers.
• Post signs warning of hot work and restrict access unless proper PPE is used.

See 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for requirements to protect other employees from welding hazards.

You must ground welding equipment properly, maintain cable and electrode insulation, and protect workers from electric shock by keeping them dry and using insulated gloves and mats where needed. Equipment should be regularly inspected and maintained to prevent electrical hazards.

• Keep electrode holders insulated and in good repair; do not touch live electrical parts.
• Ensure the work clamp has good contact with the work and that cable connections are secure.
• Replace damaged cables immediately and avoid standing in water or on wet surfaces while welding.

For electrical safety practices while welding, refer to 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing).

Employers must provide training that covers safe operation of equipment, hazards (fires, fumes, electric shock), personal protective equipment, and emergency procedures specific to welding, cutting, and brazing. Training must be sufficient for employees to perform tasks safely and follow required controls.

• Include hands-on instruction for equipment setup, cylinder handling, use of PPE, ventilation, and fire watch duties.
• Retrain when procedures or equipment change or when deficiencies in employee performance are observed.

See training and competent-person responsibilities in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for employer obligations.

Acetylene cylinders must be stored and transported upright, secured to prevent tipping, kept away from heat sources, and not used above safe working pressures; always follow manufacturer and labeling instructions. Never use acetylene above its maximum safe pressure (typically 15 psi in oxygen-acetylene systems) without proper equipment.

• Close valves when cylinders are not in use and put protective caps back on during movement or storage.
• Use flashback arrestors and check regulators and hoses for damage or leaks before use.

Refer to 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for safe handling and use of fuel-gas cylinders.

When welding in confined or enclosed spaces, you must evaluate the space for hazardous atmospheres, provide ventilation or supplied air, and use a permit system and standby personnel as needed to ensure safe entry and continuous monitoring. Confined-space welding requires extra controls because fumes and gases can accumulate.

• Test the atmosphere for oxygen level, flammable gases, and toxic contaminants before entering.
• Provide mechanical ventilation or supplied-air respirators and maintain communications and rescue capability for the worker inside.

See the requirements for controlling hazards during welding in confined spaces in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) and coordinate with confined space standards as applicable.

You must control exposures from brazing flux fumes by using local exhaust ventilation, work practices to minimize fume production, or respiratory protection when ventilation is inadequate. Employers should substitute less hazardous fluxes when feasible and provide training on safe handling.

• Use local fume extraction at the worksite and keep worker breathing zones clear of fumes.
• If respirators are required, implement a respiratory protection program with fit testing and medical evaluation.

Refer to fume control and hazard prevention measures for brazing in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing).

Before starting hot work near combustible walls or floors, you must remove combustibles or protect them with fire-resistant shields, ensure adequate clearance, and provide a fire watch if removal or shielding isn’t possible. Employers must prevent sparks and hot slag from reaching combustibles.

• Place noncombustible barriers or insulation between the work and combustible materials, and cover floor openings to prevent sparks from falling into concealed spaces.
• Inspect the area for hidden combustible materials (insulation, paper, dust) and take steps to eliminate ignition sources.

For detailed prevention and protection practices around combustibles, see 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing).

Welding curtains and screens should be positioned to block direct and reflected arc light, flying sparks, and slag from other workers while allowing ventilation and view of the work as needed. Curtains must be flame-resistant and placed to prevent bystanders from being exposed to radiated heat or ultraviolet light.

• Choose screens with appropriate opacity/shade to reduce arc flash exposure; ensure gaps don’t allow direct view of the arc for unprotected workers.
• Maintain curtains in good condition—replace torn or burned sections promptly.

See protective equipment and area control guidance in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for using welding screens effectively.

You must ensure piping or vessels are purged, cleaned, and verified free of flammable gases or vapors before starting cutting or welding; if complete removal isn’t possible, use isolation, inerting, or continuous purging to prevent explosive mixtures. A competent person should confirm the area is safe.

• Vent and purge the system with inert gas if residues of flammable gases are present and test the atmosphere to verify safe oxygen and flammable limits.
• Use continuous monitoring during hot work and keep a fire watch on hand.

Follow the control and testing procedures described in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) to prevent explosions during hot work on process equipment.

Employers must maintain welding equipment—cables, electrode holders, torches, regulators, and hoses—in safe condition and remove defective equipment from service until repaired. Regular inspections and preventive maintenance prevent failures that could cause fire, electric shock, or gas leaks.

• Inspect cables and insulation for cuts or frays, check regulator settings and hose connections, and replace worn or damaged parts immediately.
• Keep equipment clean, dry, and free of oil/grease, especially around oxygen systems.

See maintenance and inspection expectations in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for keeping welding equipment safe.

Oxygen and fuel-gas cylinders must be kept separated by distance (at least 20 feet) or by a noncombustible barrier at least 5 feet high with a fire resistance rating of at least 30 minutes when 20 feet spacing isn’t feasible. This prevents adjacent cylinders from contributing to a fire.

• Where cylinders are used together at a worksite, handle them carefully and store spare cylinders away from the work area.
• Always secure cylinders upright and close valves when not in use.

See the storage and separation requirements in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for proper cylinder placement.

If welding creates visible fumes or odors inside a building, you must control the contamination with local exhaust ventilation or respiratory protection and investigate to identify and eliminate the source. Visible fumes indicate the potential for overexposure and require immediate action.

• Stop work if necessary and install or increase local fume extraction to capture contaminants at the source.
• Evaluate the composition of the fumes (coatings, base metals) and adjust controls or PPE accordingly.

Refer to fume control requirements in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for guidance on addressing indoor welding fumes.

Workers should wear flame-resistant clothing that covers exposed skin, welding gloves, and protective footwear to prevent burns from sparks, molten metal, and hot surfaces during brazing or cutting. Clothing should be free of oil and grease to avoid ignition.

• Use long sleeves and cuffless pants made of wool or leather or treated cotton; avoid synthetic materials that can melt.
• Wear gauntlet-type leather gloves and high-top leather boots when appropriate.

See personal protective equipment and clothing recommendations in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for specific protection measures.

Employers must not perform hot work where combustible dust, lint, or explosive atmospheres are present unless the area is cleaned, tested, and made safe; if hot work is necessary, use strict controls, isolation, and a fire watch to prevent ignition and explosion. Hot work in such areas often requires special procedures and permits.

• Clean up dust and lint accumulations before starting hot work; if cleaning isn’t possible, use remote methods or inerting to prevent ignition.
• Use continuous monitoring and have emergency and firefighting equipment ready.

Consult the hazard control and hot-work guidance in 29 CFR 1910 Subpart Q (Welding, Cutting, and Brazing) for working near combustible atmospheres.