The U.S. Chemical Safety Board (CSB) issued a status-update on a February explosion at the Packaging Corporation of America (P.C.A.) plant in DeRidder, Louisiana that killed three and injured seven more. According to CSB, the 30-foot-tall tank had about 10-feet of water and flammable materials in it at the time, resulting in 20-feet of vapor space. A spark from nearby hot work got into the tank, causing combustion, and triggering the explosion.
The Leesville Daily Leader quoted CSB Chairperson Vanessa Sutherland as saying, "The CSB has investigated many hot work accidents across the country, including a 2008 explosion that killed three workers at a different P.C.A. plant in Tomahawk, Wisconsin. Hot work incidents are one of the most common causes of worker deaths we see at the CSB, but also one of the most readily preventable.” The explosion at the P.C.A. plant was initially thought to be connected to tank pressurization; the final report will be available for public viewing on the CSB website when it is complete.
Hot work is any process involving flame, spark or heat production including cutting, burning, welding, soldering, heat treating, grinding, chipping, drilling, brazing or tapping. NFPA 51B, Standard for Fire Prevention During Welding, Cutting, and Other Hot Work outlines the steps for a hot work safety program. Each hot work job requires an assessment to determine the best measures needed to safeguard workers, structures, and surrounding areas, including:
- seeking a hot work alternative;
- moving hot work to an area free from all combustible materials;
- separating hot work from combustible materials to a distance of at least 35 feet; and
- protecting materials with an approved fire resistant welding blanket, pad or curtain.
Hot work is a common practice within industrial facilities, and far too often we are seeing incidents that are easily preventable. Last August, a CSB team was dispatched to a marine terminal facility in Nederland, Texas when a hot work incident at a crude oil pipeline produced a flash fire injuring seven workers. Hot work problems also occur on construction and renovation jobsites like Trinity Street Bridge. The major artery in Pittsburgh was closed for nearly a month last fall when welding ignited a plastic pipe and construction tarp causing a fire that structurally damaged a 30-foot steel support beam.
NFPA has been working with the Boston Fire Department (BFD) and Boston Metropolitan Trades Council since last fall to deliver hot work safety awareness training for the trades. A devastating hot work fire took the lives of two Boston firefighters in 2014; and BFD asked NFPA to develop a safety awareness training program for all construction workers involved in hot work projects. To date, over 15,000 workers have been trained on hot work basics so that appropriate safeguards are established and followed at every job site in the City of Boston.