Your welding company’s method for stopping fires

Developing and following a hot work procedure is essential for any welding company looking to control their 5,000 degree arcs, compressed flammable gases, spray of sparks, and open flames that occur on a regular basis. Our welding company specializes in cell tower welding, which means we are creating sparks, arcs, and flames up to 200 ft. above dry brush, fields, and forests. The benefit of controlling these processes are decreased fires, decreased liability, welding code compliance, and the capability to easily adapt to a customer’s unique needs or hazards. Most small welding companies loathe another process or written procedure to be written, but by reading this short article, the owner (or responsible individual) can quickly and efficiently identify the primary attributes of a hot work procedure, and get closer to reaping the benefits of a well-controlled hot work process.

The gorillas in the room!

Our hot work procedure, which covers grinding, preheating, welding, brazing, cutting, and post-weld heat treating is six pages long. Three of these pages contain all of the signatures, definitions, and some industry standard guidance for fire extinguisher selection. That leaves three pages; three pages of clear and concise requirements to help our employees eliminate the gorillas in the room. Hot work is nothing new, and occurs in-control and out-of-control on thousands of jobsites daily. It’s not rocket science, and it’s not some well-kept secret. The purpose of your Hot Work procedure should be to educate and provide basic rules to everyone in your company to move you from the out-of-control region into the in-control region. By simply removing the big ticket hazards, the high risk practices, you can decrease your liability 100X, that’s a pretty high rate of return for a six page document!

The Four Gorillas

The four facets your hot work procedure needs to detail are:  control of ignition sources, control of combustibles, job assignments, and fire suppression.

Control of Ignition Sources:

These are the things we do, the things that START the unintended fires. They include the welding arc, the hot stub you just laid down, the hot slag falling out of the weld zone, the welded component as it cools down, and the spray of sparks when the fitter is grinding. There is not much we can do to control these, except for when and where we start them. In addition to deciding the time and place ignition sources will occur, we can generally control the direction of travel, and what is in their path. Attributes of control include designated containers to catch molten steel or hot stubs. Separation of combustibles from areas being heated for torch cutting or post weld heat treatment, and assigning fire watches to monitor the welding, cutting etc. to identify hazards on the spot.

Control of Combustibles:

At a given temperature, everything will ignite and burn (termed auto-ignition). Below that temperature objects can combust if an ignition source is exposed to the object. There are important terms and lines to draw, an example is our hot work procedure differentiates between a flammable liquid (flash point below 100F) and a combustible liquid (flash point at or above 100F). Flammable liquids are prohibited from being within 35 ft. of ignition sources, where combustible liquids may be adjacent to the work area, but need to be protected just as combustible solids like wood and plastics. With solid combustibles, we require removal of all combustibles, and if not possible or reasonable we require protection. Protection must be accomplished with welding screens or welding blankets. When selecting welding blankets, pay attention to the temperature ratings.  Some are made for vertical applications only, some are capable of vertical and horizontal basically rated to have hot slag sitting on the blanket while protecting any combustibles from ignition below.

Job Assignments

You would think that control of ignition sources and combustibles would be the most important attributes to a hot work process, and they very well may be. In our company we emphasize job assignments and stick to these like gospel. Most everybody has a basic understanding of ignition sources and combustibles, but if no one’s watching the coop, there’s sure to be trouble.

There are two primary players in the hot work process, the Fire Watch and the Hot Work Operator. The Fire Watch has overall control of the evolution. Our hot work procedure states they have overall control and authority to change or stop hot work at any time independent of their rank in the company. They perform the pre and post work walk downs, identify and stage fire suppression equipment, setup or oversee the covering/removal of combustibles, keep watch of the ignition sources, and are the first ones to fight an unintended fire. The Hot Work Operator is responsible for knowing the hazards they are introducing, following the procedure, listening to the Fire Watch, wearing the proper protective equipment (PPE), assisting the Fire Watch with firefighting if required.

It is very important for these job assignments to be discussed and assigned before work commences. In addition, the Fire Watch should have no other assignment that may distract them from the role of Fire Watch during hot work. The education and training is minimal, but knowing the assignment and performing it is critical.

Fire Suppression

Fire extinguishers, buckets of water, water tanks, these are all common fire suppression equipment used for welding. In addition there is fire suppression equipment if the fire grows including fire hydrants, foam, and professional firefighting outfits (like the ones that respond when you dial 911). Your hot work procedure should clearly delineate what equipment is required for your team, and at what point they need to decide a fire is out of their control, and emergency services needs to be contacted. It is important not only for their safety, but for safety of the building, field, or area you are working in. A typical requirement is that the Fire Watch must locate all fire extinguishers in the vicinity where work will be performed and have at least one 10 lb. ABC fire extinguisher within arm’s reach. If /when a fire occurs, and it is obvious to the fire watch that the current fire suppression equipment is not adequate, contacting (via a predetermined method) emergency services must occur.

In addition to addressing the four gorillas above, don’t forget to mention the pre-work walk downs which can identify additional hazards specific to the job, and the post work walk down that makes sure all ignition sources have been removed and that none of the combustibles have smoldering fires.

Now go out and melt the stuff we get paid to melt, and protect the rest with your new hot work process!

Disclaimer: The content in this blog is not intended to be used as the sole means for writing or implementing a hot work procedure. Industry guidance such as ANSI Z49.1 Safety in Welding, Cutting, and Allied Processes or NFPA 51B: Standard for Fire Prevention during welding, cutting, and other hot work should be read and understood by the responsible individual developing the program.