Seattle, WA – A man operating an arc welder near a truck fuel cell was severely burned in what police describe as a “non-organized truck repair operation.” The fuel cell apparently came loose and ignited, engulfing the victim in flames, according to the spokesman.
The mechanic, who sustained burns to most of his body, was taken to Harborview Medical Center where his condition is unknown.
Welding is a form of “hot work,” a term covering any activity that produces flames, sparks and/or heat. The wide-ranging definition includes not only obvious tasks such as welding, cutting and grinding, but also soldering, brazing, drilling (which can create heat from friction) and even thawing pipes.
Although hot work presents a number of risks, the potential for starting a fire is among the most significant. That’s why asking whether hot work is necessary and looking for alternatives are the initial recommendations from organizations such as the National Fire Protection Association and the Chemical Safety Board.
NFPA’s 51B Standard for Fire Prevention During Welding, Cutting and Other Hot Work was published in 1962, predating OSHA by nearly a decade. OSHA used that standard to craft part of its general requirements on Welding, Cutting, and Brazing (1910.252), and refers users to NFPA 51B “for elaboration.”
In the NFPA standard, the next step for safe hot work is to try to perform activities in a “designated area,” defined as “a specific location designed and approved for hot work operations that is maintained fire-safe” and “that is of noncombustible or fire-resistive construction, essentially free of combustible and flammable contents, and suitably segregated from adjacent areas.”
NFPA’s 326 Standard for the Safeguarding of Tanks and Containers for Entry, Cleaning, or Repair requires that if “flammable vapors in the atmosphere exceed 10 percent of the lower flammable limit” that work must stop in or around a tank or container. The source of that vapor must then be found and controlled or eliminated.
The standard also recommends testing “before and during any hot work, cutting, welding or heating operations” when inside or near containers or tanks that have or once held flammable or combustible liquids or gas.