WASHINGTON – The Occupational Safety and Health Administration's (OSHA) new publication, Firefighting Precautions at Facilities with Combustible Dust, includes four examples of instances where firefighters were killed or injured battling a combustible dust fire at a wood manufacturing plant.
The following examples and others involving other types of combustible dust materials are used to illustrate the dangers that emergency responders encounter in ComDust-related fires and explosions.
Maryland, 2005: four firefighters injured. A fire department responded to light smoke coming from a sawdust hopper at a boat manufacturing plant. Two firefighters opened an access door and directed a straight stream of water onto the burning sawdust. A dust cloud discharged from the door, ignited immediately, and injured both firefighters. A second team of firefighters, unable to confer with the injured firefighters, repeated the attack using the same tactics. The same sequence of events recurred and they were also injured.
Oregon, 2010: one firefighter injured. News reports indicated that a fire occurred in sawdust waste on a conveyor at a forest products plant. A spark sensor and interlock operated properly
and shut down the conveyor. When an access door was opened, the inrush of air triggered an
explosion that injured a firefighter.
Unknown location, 2004: two firefighters injured. A National Fire Protection Association
(NFPA) report on firefighter injuries described a smoldering fire in duct work at a furniture
manufacturing company. Plant personnel told the fire department that the associated dust
collector had been shut down, but it had not. Two firefighters on an aerial lift were injured
when they gained access to the duct and an inrush of air caused an explosion.
Ohio, 2003: two firefighters killed, eight injured. According to a NIOSH report, several fire departments were fighting a fire at a lumber company in an oxygen-limiting silo that was filled with wood chips. Firefighters were directing water streams through openings at the base and the top of the silo when there was an explosion. A firefighter on top of the silo and another on an aerial platform were killed (see photo). The report cited improper tactics for oxygen-limiting silos as a factor in the outcome.
Since 1980, OSHA said more than 130 workers have been killed and more than 780 injured in combustible dust explosions. The new publication describes how combustible dust explosions occur and how they might be prevented. It also explains the preparations and safeguards emergency responders can make before a response to a ComDust explosion and fire.
"This booklet will keep both emergency response and facility workers safe by giving them a framework to prepare for potential emergencies involving combustible dust," said Dr. David Michaels, assistant secretary of Labor for OSHA. "Stakeholders that have reviewed the booklet, including fire chiefs and union health and safety representatives, describe it as 'an excellent resource for explaining the hazards associated with combustible dust and outlining the best practices for pre-incident operational preparation by emergency responders.'"
Wood dust is among a list of materials considered a combustible dust. Others iniclude plastic, rubber, coat, flour, sugar and paper.