Lithium-Ion Batteries Stored in Plastic Toolboxes Started the Dorchester Fire Where Firefighter Bobby Kilduff Died, Officials Say

The three-alarm fire on Treadway Road in Dorchester where Boston firefighter Robert "Bobby" Kilduff Jr. died in May was caused by thermal runaway in multiple lithium-ion batteries stored in plastic toolboxes, Boston Fire Commissioner Rodney Marshall said Wednesday.

Speaking at Boston Fire Department headquarters, Marshall said investigators determined the fire began in the rear of the building on a third-floor porch, WCVB reported.

Kilduff, a 24-year veteran of the department, a third-generation firefighter and a U.S. Marine veteran, fell from the third story of the home during the May 23 fire, according to WCVB and Boston 25 News. He was taken to Boston Medical Center, where he was pronounced dead.

Two inquiries continue

The finding closes the cause-and-origin investigation only. The National Institute for Occupational Safety and Health and the department's Board of Inquiry are conducting parallel investigations into the circumstances of Kilduff's death, Marshall said. "We will allow these processes to proceed without speculation or premature conclusions," he said, according to WCVB.

Facts and findings from those investigations will be released when they are complete, Boston 25 News reported, citing the fire marshal.

"We recognize this incident has had a profound impact on this department, the Kilduff family, and the entire Boston community," Marshall said, according to Boston 25 News.

Battery warnings

Marshall said lithium-ion batteries must be charged, handled and stored according to manufacturer recommendations and established safety guidelines. District Fire Chief Keith Kelly of the department's Special Operations Command told Boston 25 News, "I don't want to scare people away from them, but they do pack a lot of energy. As long as you're using them properly with the recommended packages' guidelines, they're safe."

Fire officials advise against charging batteries on a bed or sofa, and say damaged batteries should not go in the trash but to a battery drop-off location, WCVB reported.

Tributes

"Bobby Kilduff gave his life in the line of duty doing what our firefighters do every day, putting themselves in harm's way to protect their neighbors in our community," Mayor Michelle Wu said Wednesday, according to Boston 25 News. She said the city is working on efforts to honor his legacy and support his family.

Sam Dillon, president of Boston Firefighters IAFF Local 718, told Boston 25 News, "You can't replace a Bobby Kilduff. Not in the fire union, not in the fire service, not in life."

Additional reporting

Robert Kilduff Jr., a third-generation firefighter and U.S. Marine veteran, died while responding to a fire on Treadway Road in Dorchester in May after falling from a third-floor porch. He was rushed to the hospital, where he later died from injuries sustained in the fall.

“We recognize this incident has had a profound impact on this department, the Kilduff family, and the entire Boston community,” said Boston Fire Commissioner Rodney Marshall. “We thank the family and the community for their patience as our investigators worked diligently to establish the origin and cause of this fire.”

Investigators determined the fire was caused by thermal runaway involving multiple lithium-ion batteries stored in plastic toolboxes. “These batteries much be charged, handled and stored in accordance with the manufacturer’s recommendations and established safety guidelines,” said Marshall. “Improper charging or storage can create serious fire hazards.”

Kelly offered several steps people can take to reduce the risk of fires: Although the investigation into the cause and origin of the fire is complete, investigations into Kilduff’s line-of-duty death remain ongoing. The National Institute for Occupational Safety and Health is conducting one investigation, while the Boston Fire Department Board of Inquiry is conducting another into the circumstances surrounding Kilduff’s death.

“Bobby Kilduff gave his life in the line of duty doing what our firefighters do every day, putting themselves in harm’s way to protect their neighbors in our community,” said Mayor Michelle Wu on Wednesday. “He made the ultimate sacrifice in service to our city and were continuing to work on several efforts to honor his legacy and support his family.

Facts and findings from the investigations into Kilduff’s death will be released once they are complete, according to the fire marshal. Sam Dillon, president of Boston Firefighters IAFF 718, spoke to Boston 25 about Kilduff Jr. moments after the details were shared. “You can’t replace a Bobby Kilduff,” he said. “Not in the fire union, not in the fire service, not in life. He was truly one of a kind.

Dillon said Kilduff Jr. saved lives in Dorchester that night in May. He finished, “Take hope and comfort away from this that there are men like Bobby Kilduff who are willing to put their life on the line and are willing to give their life to something they believe to be more important than themselves.”

What is still unknown

Officials have not said what devices the batteries powered, who owned them, or when the NIOSH and Board of Inquiry reports are expected.