Hot Work – Practices to Control High Fire Risk

On the date of the fire, a plumber was repairing a leak in a pipe elbow in a remote area. After pulling most of the foam insulation away, he finished soldering and left. Someone spotted smoke an hour later. No fire extinguisher was available; the fire continued to spread, eventually destroying the building.

This was a common fire loss from a hot work situation that resulted in a total building loss and severe business interruption. Fortunately, no one was injured; however, like most hot work situations, this fire could have been  prevented by following basic hot work practices.

“Hot work” describes work that produces heat or sparks and takes place outside of the controls found in normal work areas. Factors of hot work fires include delayed detection, working near combustible material, and a lack of nearby fire extinguishers.

Hot work examples include:

• Grinding or cutting near combustible material.
• Heating pipes to thaw or loosen them.
• Hot riveting.
• Using Powder-driven fasteners or tools.
• Welding and heating material, including brazing and soldering.

Management is responsible for developing and enforcing a hot work policy and training employees.

Elements of a hot work program include:

• Identify and record all hot work tasks that are completed by company or subcontractor employees. The policy must be maintained to cover new work situations or operation changes that alter the hazards. This includes non-routine maintenance or repair situations.
• Keep a detailed log of all hot work that is conducted, including when the work is completed.
• The program must use a permit system with an authorized person or department that is responsible to issue permits. The person who issues the permit is known as the permit authorizing individual, or PAI, who must be trained and controls the hot work situation.
• Management must ensure that all internal employees and external contractors are familiarwith the facility’s hot work procedures and the permit system process. The PAI should be made aware when any contractors are brought on site to discuss and review the procedures with the contractor’s on-site supervisor.
• All employees who participate in hot work must be trained, including subcontractors.
• Training should be redone when tasks or responsibilities change.
• Purchase and ensure that fire extinguishers and protectice equipment are available and kept in good condition.

The permit system involves a tag or permit, which is issued to the employee or contractor performing the hot work. The permit is issued and signed by the PAI and must hang in the hot work area until the work is completed. A permit is good for one day and a new permit must be issued if the work ends on the same shift and is restarted later.

General controls for conducting hot work include:

Precautions within 35 feet of work:

• All wall and floor openings are covered.
• Combustible floors are wet down, covered with damp sand, metal, or fire-proof material.
• Combustible materials or flammable liquids are removed from the area or protected with fire-proof material.
• Ducts, conveyors, or vent systems that may carry sparks to other areas are covered, shut down, or protected.
• Floors are swept clean of combustibles.

Work on walls or ceilings:

• Combustibles on the other side of wall or ceiling are moved away from wall.
• Construction is noncombustible and does not have any combustible covering or insulation.

Work on enclosed equipment:

• Containers are purged of flammable vapors or liquids.
• Equipment is cleaned of all combustibles (product, dust, waste).
• Pressurized vessels, piping, and equipment is properly de-energized and locked out.

Fire watch:

• Extinguishers or a small hose with a water supply is readily available.
• A fire watch is needed in adjacent areas or floors. Fire watch should be extended beyond 30 minutes based on PAI.
• Individuals are trained in use of equipment, when/how to sound alarm, and other means of communication.
• Individuals are trained in use of equipment, when/how to sound alarm, and other means of communication.
• Fire watch is provided during operation and for 30 minutes after operation is complete.
  

Additional Controls:

• Appropriate ventilation is provided. When working in confined spaces, a permit must be issued.
• Personal protection from electrical shock from wet floors is available.
• PPE used as needed (i.e. eye protection, helmet, protective clothing, respirator, gloves).
• Special controls followed for hot work on metal vessels or piping lined with rubber or plastic.
• Warning signs posted to warn other workers of hot work area.

Remember, major fires have started from short tasks or even from work that seems incidental that involve hot work situations and no task should be taken for granted. Here is a sample hot work permit which can be used.

The purpose of this report is to assist you with your risk management practices. Keep in mind that other exposures may exist. This report does not address every loss-producing condition that exists currently or that may develop in the future.