Hot work is defined as welding, cutting, grinding, or other spark-producing activities that can ignite flammable substances. To date in 2010, CSB has learned of 15 serious hot work-related fires and explosions that caused six reported fatalities and numerous injuries.
“I am saddened by this accident and disturbed that such fatalities continue to occur,” Moure said. “The CSB is vitally concerned about hot work accidents and this was expressed in our important safety bulletin and safety video, both issued within the past few months.”
According to information gathered by CSB from the fire department and the company, a worker was standing on a ladder, welding on the side of a tank partially filled with a mixture of water and flammable hydrocarbons. Sparks ignited flammable vapor and the worker was thrown off the ladder, suffering fatal injuries.
The company stated that although it has a hot work permit system and had provided safety training to the victim, there was no monitoring for a flammable atmosphere before or during the welding. While current OSHA standards prohibit hot work in an explosive atmosphere, OSHA does not explicitly require the use of combustible gas detectors.
The CSB safety bulletin, “Seven Key Lessons to Prevent Worker Deaths During Hot Work In and Around Tanks” is subtitled “Effective Hazard Assessment and Use of Combustible Gas Monitoring Will Save Lives.” The bulletin noted there have been more than 60 fatalities since 1990 due to explosions and fires from hot work activities on tanks. In seven of the 11 accidents discussed in the bulletin, no gas testing was performed prior to or during the hot work activities. In the remaining cases, monitoring was conducted improperly.
“There is no secret to preventing these accidents. Companies should require effective monitoring of the atmosphere before and during all welding or other spark-producing activities near tanks that may contain flammable liquids or gases,” Moure said. “Monitoring should be frequent or continuous and performed at multiple locations to assure that no flammable vapor is present which could be ignited. Monitoring the atmosphere and following the other six key lessons in our bulletin can help avoid these tragedies.”