Chemical Safety Board Reports on Hot Work Hazards

Don’t get hot work confused with working in the heat.  There is a lot of difference.  Hot work involves burning, welding, cutting, brazing, grinding, soldering and similar operations that are capable of initiating fires or explosions. While the Occupational Safety and Health Administration (OSHA) has established hot work standards in 29 CFR 1910.252, deaths and serious injuries still occur during hot work-related procedures.

Hot work accidents are reported more frequently in the oil and gas industry, where flammables are handled. They may also occur in other industries as well, such as, food production, paper, and wastewater treatment industries.  It is one of the most common causes of work related fatalities investigated by the Chemical Safety Board (CSB).

Recently, the CSB identified over sixty fatalities that have occurred since 1990 while hot work tasks were being preformed.  Following is a summary of just a few of these accidents.

Two employees using an oxygen-acetylene torch, to loosen a tight fitting, on what was thought to be an empty fuel tank were severely burned.  The tank contained residual hydrocarbon and had not been cleaned or purged prior to performing hot work procedures.  The fire and explosion that occurred resulted in both employees being airlifted to a regional burn center, where they were treated for burns covering 30 to 50% of their bodies.

An explosion killed two contract workers while they were welding on a crude oil storage tank. The explosion occurred when the workers attempted to weld a bracket on top of one of the tank, near an atmospheric vent. Because the tanks were interconnected, oil flowing into an adjacent tank likely displaced flammable vapor into the tank being welded. The vapor escaped through the vent and was ignited by welding sparks.

A contract welder was killed while welding on a catwalk located over a waste oil storage tank. An investigation by the local fire department concluded that, during welding, sparks were allowed to drop in and around the vent area of the tank. The contents of the tank ignited, resulting in an explosion and fire. The force of the explosion threw the contract welder about 120 feet, fatally injuring him.
Additional examples could be provided, but the message would be the same.  Hot work can dangerous when safety precautions are neglected.  Prior to conducting hot work the CSB recommends that a hazard assessment be conducted and that monitoring for combustible gases be preformed.

The CSB has produced a 14-minute video on the hazards hot work involving storage tanks containing flammable materials.  The video uses 3-D computer animation to depict three hot work accidents. The video is available on the CSB’s website at  http://www.csb.gov/investigations/detail.aspx?SID=93.  A copy of the CSB report is available at LEPC NEWS:  http://lepcnews.squarespace.com/hot-work-hazards/.