The fire suppression system aboard the USS Bonhomme Richard was inoperable Sunday when flames engulfed the ship in San Diego, according to a top Navy official on Monday.
The Halon gas system “was not in operation just because it was being worked on” while the amphibious assault ship was undergoing maintenance at the shipyard, said Rear Adm. Philip Sobeck, the commander of Expeditionary Strike Group 3.
Halon, a liquefied compressed gas that disrupts the chemical process of a fire, is used aboard commercial flights and Navy ships, as it leaves no residue, protecting valuable electrical equipment in the event of a fire.
Navy officials first reported the blaze on Sunday morning in a lower cargo area, and the fire was still burning as of Monday evening.
At least 59 people, 36 sailors and 23 civilians, have been treated for injuries, including heat exhaustion and smoke inhalation, with five still hospitalized for observation. Roughly 160 sailors and officers were on board when the fire started.
Sobeck said it began in a large storage area where cardboard and drywall supplies were kept. Local, base and shipboard fire fighting teams first tried to quell the blaze with water but were forced to pull back.
The Navy has not yet given a cause for the fire, and an investigation is underway.
Sobeck said fire had “spread throughout the ship” but that the Navy is “doing everything we can” to save the vessel.
“We’re assessing the extent of the damage and that’s going to be ongoing. Once we get the fire out, which is the priority, we’ll then make a complete assessment,” he said.
The fire has also raised environmental concerns, as the blaze has sent smoke clouds over San Diego — with local officials recommending people avoid outdoor exercise — and the Coast Guard has contracted an Oil Spill Response Organization to preemptively guard against any potential fuel spills or other debris.
“A one-nautical mile safety zone has been established to ensure the safety of the maritime public,” Cmdr. Chris Wright, the response department head of the San Diego Coast Guard, said in a statement on Monday.