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Course 745 - Welding, Cutting, and Brazing Safety

Safety guides and audits to make your job as a safety professional easier

Welding Best Practices and Precautions

best practices

Importance of Welding Location

The first consideration for safety in welding is the location and peculiarities of the space in which the welding operation is to be performed.

Weld or cut only in locations specifically designated for this purpose unless you have obtained approval of the job and have taken the necessary precautions to eliminate fire and explosion hazards.

Do not weld in any location outside the shop unless you take the necessary precautions and get authorization. Before you weld in any compartment, room, tank, or adjacent space which contains or which has contained flammable or explosive materials, liquids, or vapors, make sure they are:

  • made safe,
  • tested, and
  • proclaimed safe.

These restrictions also apply to closed drums, tanks, and similar containers.


Welding Safety 101 - ChuckE2009
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Allow welding or cutting only in areas that are or have been made “fire safe.”

  • When you cannot move work practically, as in most construction work, the area must be made safe by removing combustibles or protecting combustibles from ignition sources.
  • If you cannot remove fire hazards, install suitable guards, or take special precautions as discussed below, then welding and cutting should not be performed.
  • If you cannot move the object to be welded or cut and if not all the fire hazards can be removed, use guards to confine the heat, sparks, and slag, and to protect the immovable fire hazards.

Prohibited Areas

Do not permit welding or cutting in the following situations:

  • in areas not authorized by management
  • in sprinklered buildings while such protection is impaired
  • in the presence of explosive atmospheres (mixtures of flammable gases, vapors, liquids, or dust with air)
  • inside uncleaned or improperly prepared tanks or equipment which have previously contained such explosive atmospheres or have the potential for explosive atmospheres
  • in areas with an accumulation of combustible dust
  • in areas near the storage of large quantities of exposed, readily ignitable materials such as bulk sulfur, baled paper, or cotton

Fire Prevention and Protection

fire prevention

Eliminate fire and explosion hazards by removing or reducing combustible or explosive materials or vapors by preventing them from accumulating. The methods for making a space safe for welding and the tests used to ensure a space is free of fire and explosion hazards should be the responsibility of a welding supervisor.

Special Precautions for Fire Prevention

Combustible material: Wherever there are floor openings or cracks in the flooring that you cannot close, you should take precautions so no readily combustible materials on the floor below is exposed to sparks that might drop through the floor. Use the same precautions for cracks or holes in walls, open doorways and open or broken windows.

Combustible covers: Never weld on a metal partition, wall, ceiling or roof having a combustible covering nor on walls or partitions of combustible sandwich-type panel construction.

Relocation of combustibles: If possible, relocate all combustibles at least 35 feet (10.7 m) from the work site. When relocation is not possible:

  • protect combustibles with flame-proofed covers, or
  • shield combustibles with metal or asbestos guards or curtains.

Floors: Where combustible materials such as paper clippings, wood shavings, or textile fibers are on the floor, sweep the floor clean within a radius of 35 feet (10.7 m). In addition:

  • If floors are combustible, keep them wet, covered with damp sand, or protected by fire-resistant shields.
  • Protect workers operating arc welding or cutting equipment from shock where floors have been wet down.

Ducts: Protect or shut down ducts and conveyor systems that might carry sparks to distant combustibles.

Combustible walls: Where cutting or welding is done near walls, partitions, ceiling or roof of combustible construction, provide fire-resistant shields or guards to prevent ignition.

Non-combustible walls: If you need to do welding on a metal wall, partition, ceiling or roof, prevent ignition of combustibles on the other side, preferably by relocating combustibles. Where you are not able to relocate the combustibles, be sure to provide a fire watch on the opposite side from the work.

Pipes: Do not cut or weld on pipes or other metal in contact with combustible walls, partitions, ceilings or roofs if the work is close enough to cause ignition by conduction.

Fire extinguishers: Position suitable fire extinguishing equipment and maintain it in a state of readiness for instant use. Depending on the nature and quantity of the combustible material, fire-extinguishing equipment may consist of:

  • pails of water,
  • buckets of sand,
  • hoses, or
  • portable extinguishers.

Hot Work

hot work

Hot work is any work that involves burning, welding, using fire- or spark-producing tools or that produces a source of ignition. Follow these general best practices below for hot work.

  • Do not perform hot work where flammable vapors or combustible materials exist.
  • Relocate work and equipment outside of the hazardous areas, when possible.
  • Make suitable fire-extinguishing equipment immediately available in a state or readiness. The equipment may consist of pails of water, buckets of sand, hose, or portable extinguishers dependent upon the nature and quantity of the combustible material exposed.
  • When performing hot work, assign a fire watch to guard.

Fire Watch: A worker designated as the "Fire Watch" is required whenever welding or cutting is performed in locations where other than a minor fire might develop, or any of the following conditions exist:

  • Appreciable combustible material, in building construction or contents, closer than 35 feet (10.7 m) to the point of operation.
  • Appreciable combustibles are more than 35 feet (10.7 m) away but are easily ignited by sparks.
  • Wall or floor openings within a 35-foot (10.7 m) radius expose combustible material in adjacent areas including concealed spaces in walls or floors.
  • Combustible materials are adjacent to the opposite side of metal partitions, walls, ceilings, or roofs and are likely to be ignited by conduction or radiation.

Fire Watch Duties: The duties of a qualified fire watch include:

Dangers of Hot Work – CSB.
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  • They must have fire-extinguishing equipment readily available.
  • Train them in how to use fire-extinguishing equipment.
  • They must be familiar with facilities for sounding an alarm in the event of fire.
  • They must watch for fires in all exposed areas, try to extinguish them only when obviously within the capacity of the equipment available, or otherwise sound the alarm.
  • They must maintain a fire watch for at least a half hour after completion of welding or cutting operations to detect and extinguish possible smoldering fires.

Welding or Cutting Containers

Drum Explodes During Welding, Killing Worker – WorksafeBC.
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Used containers: Do not weld, cut, or perform other hot work on used drums, barrels, tanks or other containers until you clean them.

  • Clean them so thoroughly to make absolutely certain there are no flammable materials present or any substances such as greases, tars, acids, or other materials which when subjected to heat, might produce flammable or toxic vapors.
  • Disconnect or blanket any pipelines or connections to the drum or vessel.

Venting and purging: Vent all hollow spaces, cavities or containers to permit air or gases to escapte before preheating, cutting or welding. You should purge with inert gas.

Shielding Gas Safety

Shielding gases are inert or semi-inert gases such as argon, helium, and carbon dioxide used in welding processes to protect the weld the molten metal from the contamination and oxidation. Damage to the weld can be caused by harmful gases such as nitrogen, oxygen and water vapor in the atmosphere. Air in the weld zone is displaced by a shielding gas in order to prevent contamination of the molten weld puddle.

The types of welding in which shielding gases are use include Metal Inert Gas (MIG) and Tungsten Inert Gas (TIG) welding. Improper choice of a welding gas can lead to a porous and weak weld, or to excessive spatter.

The hazards involved in using shielding gases involve primarily handling gas cylinders. For more information on compressed gas cylinder safety, see OSHA's Small Business Handbook.


Before beginning this quiz, we highly recommend you review the module material. This quiz is designed to allow you to self-check your comprehension of the module content, but only focuses on key concepts and ideas.

Read each question carefully. Select the best answer, even if more than one answer seems possible. When done, click on the "Get Quiz Answers" button. If you do not answer all the questions, you will receive an error message.

Good luck!

1. The first consideration for safety in welding is the _____.

2. Welding or cutting should be permitted only in areas that are or have been made _____.

3. Welding should not be accomplished inside uncleaned or improperly prepared tanks or equipment which have previously contained _____.

4. Which of the following is defined as any work that involves burning, welding, using fire- or spark-producing tools, or that produces a source of ignition?

5. What is required when appreciable combustible material is closer than 35 feet (10.7 m) to the point of the welding operation?

Have a great day!

Important! You will receive an "error" message unless all questions are answered.