Human Element

Understanding the Hazard

Hot Work

The Hazard Businesses become successful because their management takes calculated risks based on research and planning. Yet every day these same businesses put themselves at unnecessary risk by failing to control hot work ignition sources within their facili-ties. Management of hot work is smart business practice. Considering all the hazards uncontrolled hot work ignition sources can create in a facility, tolerating that risk can be one of the most expensive business decisions a company ever makes.

Science of the Hazard Virtually every facility—whether its use is commercial, industrial, educational or health care—contains a sufficient quantity of combustible material to support a fire capable of bringing operations at that facility to a halt. The combustible material may be present in the contents of the facility or in its very construction.

Combustible contents include furnishings and production equipment, storage of raw materials, finished products, packaging, ignitable liquid, flammable gas, and combustible dust or lint.

Combustible construction can range from wood to plastic building materials that are not FM Approved. Combustible building materials can be found in the walls and roof of a building, on or above ceiling tiles, and around or in heating, ventilation and air-conditioning ductwork.

With combustible material and oxygen present, only one thing is missing to cre-ate fire: an ignition source. Hot work is any operation that involves an open flame or produces heat and/or sparks, including torch and radial saw cutting, grinding, brazing, soldering, welding and torch-applied roofing. The ignition sources as-sociated with these operations are easily capable of igniting most combustible or flammable materials found within a facility, as illustrated in the following tables.

Material Ignition Temperature

Wood products 410°F to 930°F (210°C to 499°C)

Polyurethane foam (rigid) 1,020°F (549°C)

Ethanol 690°F (366°C)

Gasoline 570°F to 660°F (299°C to 349°C)

Motor oil 450°F (232°C)

Paraffin wax 470°F (243°C)

This brochure is made available for informational purposes only in support of the insurance relationship between FM Global and its clients. This information does not change or supplement policy terms or conditions. The liability of FM Global is limited to that contained in its insurance policies.

Hot work creates a ready ignition source for combustible and flammable materials. The way you manage hot work in your facility can make the difference between a temporary hazard and a major risk to your business’s future.

UTH topic categories:

n Constructionn Equipmentn Fire Protection

Human Elementn Natural Hazardsn Process Hazards

This series of publications is designed to help you understand the everyday hazards present at your company’s facilities. For more information on how you can better understand the risks your business and operations face every day, contact FM Global.

page 1 of 4

What You Can Do at Your Facility

Now:n Establish a formal, written policy for

managing hot work conducted by both employees and contractors.

n Consider using alternative cold work methods or relocating the work to a hot work designated area.

n Implement the FM Global Hot Work Permit System when conducting hot work outside a hot work designated area.

n When provided, ensure fire protection systems remain in service during the work and post-work fire watch and monitoring periods.

n Know your construction and occupancy fire hazards, and properly safeguard them when within the hot work area by:

● removing combustibles from the hot work area, which is often defined by the 35-ft. (10-m) rule; and

● covering combustibles that cannot be removed from the hot work area with FM Approved welding pads and blankets.

n Confine hot work ignition sources within the hot work area by safe-guarding ventilation systems and shutting down conveyor systems.

n Restrict hot work in areas identified as hot work high-risk areas and, when un-avoidable, provide additional required precautions on the Hot Work Permit to further minimize the likelihood or consequences of a fire or explosion.

n Provide a continuous fire watch to supervise the hot work operation as well as the hot work area to ensure the required precautions selected on the Hot Work Permit remain in place.

n Require all contractors to follow the hot work management program, including recognizing the forms of hot work covered by the program.

n Call your local FM Global office or client service team if you have any questions about planned hot work activity.

Hot Work Heat Source Temperature

Electric arc10,350°F to 21,150°F

5,732°C to 11,732°C

Arc welding slag

6,350°F at welding location

4,900°F at 1.5 ft. away

4,000°F at 16 ft. away

3,510°C at welding location

2,704°C at 0.5 m away

2,204°C at 4.9 m away

Welding spatter

3,350°F near welding rod

2,850°F at 9 ft. below welding rod

1,843°C near welding rod

1,566°C at 2.7 m below welding rod

Oxyacetylene cutting slag3,800°F

2,093°C

Sparks from grinding wheel on steel3,362°F in air

1,850°C in air

Loss Experience Hot work is a leading cause of fire and explosions throughout the world. FM Global loss history clearly shows there is no industry or type of facility immune to this hazard. Hot work is one of the three most common causes of fire at FM Global’s client properties. In a recent 20-year period, FM Global clients reported 736 hot work losses for a staggering gross loss cost of more than US$1.9 billion—an average of US$2.6 million per loss. And each loss was preventable.

All Hot Work Fires Are Preventable There are many points in the hot work process at which people have the oppor-tunity to prevent a fire or explosion. Effective hot work management starts at the top. When management understands the hazard involved and is committed to mitigating the fire risk created every time hot work is conducted, hot work losses are preventable. But, being able to implement an effective management program for any human element process requires support from all the employees involved. The key is teamwork, education and a clear understanding of the associated haz-ards and risks.

The goal of a hot work management program is to prevent hot work ignition sources from contacting combustible or flammable materials. An argument can be made that any hot work fire, even those detected and extinguished during the post-work fire watch and/or fire monitoring period is a failure of the hot work management program due to the inability to control both fuel and hot work igni-tion sources.

Understanding the Hazard: Hot Work page 2 of 4

But What About… ...FM Global’s hot work permit system requirement for a 30-minute or 60-minute post-work fire watch followed by a fire monitoring period? You’re the only organization I know of that wants to occupy my staff that long. In an effort to partner with our clients to develop effective hot work management programs, FM Global Property Loss Prevention Data Sheet 10-3, Hot Work Man-agement, has been updated to provide customized guidance on hot work permit post-work fire watch and fire monitoring periods. The fire watch and monitoring periods are based on the combustibles present within the proposed hot work area. In some cases, the post-work fire watch period might be as short as 30 minutes with no fire monitoring period needed.

But hot work loss experience has provided valuable information to support requirements for an extended fire watch and monitoring. FM Global analyzed its clients’ fire and explosion losses where the probable cause was hot work, and found 90 incidents in which a sizable fire occurred after work was completed. In these losses, approximately 50 percent were detected within 60 minutes of work completion, while another 25 percent were detected within one to four hours of work completion. With approximately three-quarters of the post-work fires occur-ring several hours after work completion, loss data supports the need for a vigilant post-work fire watch followed by fire monitoring. While the primary objective of effective hot work management is to prevent all fires or explosions resulting from hot work, people make mistakes and providing a fire watch and fire monitoring helps to counteract poor fire prevention judgment that can and will occur.

…our lack of personnel? Hot work is a hazardous operation under the best of conditions. Taking shortcuts when safeguarding the hot work area only increases the risk of fire at your facility. Because hot work is often conducted during off shifts, on weekends and outside normally occupied areas of your facility (e.g., roofs), the risk is further increased because a fire is more likely to go unnoticed in these normally unattended areas. Management needs to make a commitment to have hot work areas supervised at all times. If adequate personnel cannot be spared to manage hot work permitting, delay this hazardous work until it can be properly performed and supervised.

…the fact hot work is not performed at our facility? Hot work may not be performed today, tomorrow or next week, but what about several months from now? No facility is completely exempt from hot work unless management has absolutely restricted this type of work and requires alternative cold work methods.

Understanding the Hazard: Hot Work page 3 of 4

Alternative Cold Work Methods n Install equipment assembled with

mechanical connections instead of welded connections.

n Design changes for existing equip-ment—bolted assembly instead of welded.

n Use alternative equipment: ● A reciprocating saw, manual

hydraulic shears or a hand saw instead of a cutting torch or powered radial saw

● Self-tapping screws instead of tack welding or brazing

● Threaded pipe instead of sweat-soldered pipe

Hot Work Designated Area

Designate an area that is specifically constructed, protected and arranged to accommodate safe hot work. These areas do not require any permit system, but appropriate firesafe conditions must be maintained within them at all times.

Ordering InformationFor additional copies of Understanding the Hazard publications, contact your FM Global engineer or client service team.

Additional FM Global brochures and educational material can be found in the FM Global Resource Catalog and ordered or downloaded online at fmglobalcatalog.com. Or, for personal assistance worldwide, contact our U.S.-based customer services team, Monday – Friday, 8 a.m. – 5 p.m. ET :n Toll-free: (1)877 364 6726

(Canada and United States)n By phone: +1 (1)401 477 7744n By fax: +1 (1)401 477 7010n E-mail: customerservices@fmglobal.com

P0032 © FM Global, 2010(Rev. 12/2016) All rights reserved.fmglobal.com

FM Insurance Company Limited 1 Windsor Dials, Windsor, Berkshire, SL4 1RS Authorized by the Prudential Regulation Authority and regulated by the Financial Conduct Authority and the Prudential Regulation Authority

Need More Information?

Ask your FM Global engineer or client service team about the following: n Exemplary hot work management

in similar-sized facilities n Contractor management strategies n Effective use of the FM Global

Hot Work Permit System n FM Global Property Loss Prevention

Data Sheet 10-3, Hot Work Management

Understanding the Hazard: Hot Work page 4 of 4

Also, hot work operations may go unrecognized as such because it is more than just torch cutting and arc welding. Other, less obvious forms of hot work are often overlooked and, consequently, go unmanaged. Which of the following hot work scenarios might be conducted in your facility?

n A roofing contractor uses a propane torch or electric hot plate to heat-seal around roof drains or vent pipes.

n Maintenance personnel use a propane torch to sweat-solder copper fittings on refrigerant lines in an air-conditioning system.

n A contractor uses an electric heat gun during renovation to remove wall coverings.

The trend toward outsourcing facility and maintenance services further compli-cates the issue of unrecognized hot work. Contractors may have expertise in the services they provide, but they don’t know about the specific hot work policy (restricted hot work operations) or fire hazards present on-site, or they may not recognize the tasks they are doing as hot work.

Know the Hot Work Requirements Hot work management is not just good business sense, it’s often a requirement of local codes or national standards, such as those produced by the U.S. Occupation-al Safety and Health Administration (OSHA). Check with your local, state and national government to see what requirements govern hot work in your area.

Don’t Let This Happen to You

Failure to properly manage hot work can result in a catastrophic fire.