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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 welding and cutting precautions also apply to closed drums, tanks, and similar containers.

Restrictions and Prohibited Areas

Click on the buttons to review restrictions and prohibited areas related to welding or cutting.

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.

Do not permit welding or cutting in the following areas and 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; and
  • in areas near the storage of large quantities of exposed, readily ignitable materials such as bulk sulfur, baled paper, or cotton

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.

1. Before you weld in any space that contains flammable or explosive materials, liquids, or vapors, make sure they are _____.

a. purged and monitored
b. approved and designated
c. safe and tested
d. blocked off and watched

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Precautions for Preventing Fires

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.

2. Keep all combustibles at least _____ from the welding worksite.

a. 10 feet (3.0 m)
b. 20 feet (6.9 m)
c. 35 feet (10.7 m)
d. 50 feet (15.2 m)

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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:

Click on the buttons to review the conditions that require a fire watch and the duties of a worker designated as the Fire Watch.

Conditions. A fire watch must be on duty whenever the following conditions are met.

  • 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:

  • 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 30 minutes ( to meet OSHA requirements) or 60 minutes (to meet NFPA requirements) after completion of welding or cutting operations to detect and extinguish possible smoldering fires.

3. To meet OSHA requirements, how long must a fire watch remain on duty after completion of welding or cutting operations?

a. 15 minutes
b. 30 minutes
c. 45 minutes
d. 60 minutes

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Welding or Cutting Containers

Drum Explodes During Welding, Killing Worker – WorksafeBC.
Click to play video

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 escape before preheating, cutting or welding. You should purge with inert gas.

4. When can you weld, cut, or perform hot work on used drums, barrels, tanks, or other containers?

a. After you clean them
b. Never
c. When properly labeled
d. If approval is granted

Check your Work

Read the material in each section to find the correct answer to each quiz question. After answering all the questions, click on the "Check Quiz Answers" button to grade your quiz and see your score. You will receive a message if you forgot to answer one of the questions. After clicking the button, the questions you missed will be listed below. You can correct any missed questions and check your answers again.

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