Key facts
- Firefighters used water injection tactics on a silo fire at Robbins Lumber mill.
- The silo was oxygen-limiting, a type known to become pressurized with combustible gases during a fire.
- The tactic likely created an explosive mixture by entraining oxygen and suspending dust.
- The explosion killed three people, including two firefighters and a mill co-owner.
- At least 13 people were injured in the blast and subsequent fire.
- Federal investigators recommended improved training on silo fire hazards and appropriate tactics.
Federal investigators have determined that firefighting tactics employed at a Maine lumber mill explosion inadvertently contributed to the blast that killed three people. The National Institute for Occupational Safety and Health (NIOSH) reported that firefighters attempted to extinguish a fire inside a silo at the Robbins Lumber mill by injecting water, unaware of manufacturer warnings that this action was dangerous.
According to the NIOSH report, the silo was oxygen-limiting, a type of sealed structure that can accumulate combustible gases during a fire. The report states that the application of water likely forced air into the silo, stirred up dust, and created an explosive concentration. This hazard is known, and guidance exists warning against introducing water or foam into such chambers.
The explosion, which occurred on May 15, hurled workers and firefighters and engulfed the area in flames. In addition to the three fatalities, at least 13 people were injured. The mill company has stated it is working with industry experts to rebuild and enhance safety measures, aiming to exceed current standards.
Representatives for Searsmont Fire & Rescue did not immediately respond to requests for comment. The Maine State Fire Marshal’s Office previously indicated that the explosion was caused by the rapid ignition of particulate material, lifting the silo from its base and releasing sawdust. The town of Searsmont noted that investigations are ongoing and urged against premature judgments, emphasizing the dedication of the first responders and the company's loss.