NEW YORK (PIX11) – An FDNY firefighter is not expected to survive a serious head injury he sustained in a 20-foot fall at his Brooklyn firehouse earlier this week, officials announced on Friday.

William Moon, 47, fell on Monday just before noon while preparing for a fire drill at his firehouse on Sterling Place. The 21-year FDNY veteran was treated for his injuries by his fellow firefighters before being rushed to Kings County Hospital in critical condition.

Doctors determined Friday morning that Moon would not be able to overcome his injuries, Mayor Eric Adams and Fire Commissioner Laura Kavanagh announced in a joint statement. During a news briefing, Kavanagh shared a statement from Moon’s wife, Kristina.

“Loving Billy was not only a marriage of families but a marriage to the fire department. His love and passion for the job extended far from the firehouse walls. He instilled that same passion in our children and how important it was to help others. We are eternally grateful for the Christmas miracles that Billy will be able to give others.”

Kristina Moon

His family plans to donate his organs to save the lives of others.

“Firefighter Moon is a hero twice over,” Mayor Adams said, referencing the organ donation. “He’s spent 21 years saving the lives of his fellow New Yorkers and he will continue to save lives in his passing.”

Moon began his career in Ladder Company 133 in Queens, where he worked for 20 years before being detailed to Rescue Company 2, in Brooklyn earlier this year, according to the FDNY. Moon also served as a member of the Islip Volunteer Fire Department, where his family lives on Long Island.

“Our hearts are broken for firefighter Moon’s family and friends, and for our entire department. He spent his life helping others, here at the FDNY, and on Long Island, as a volunteer fire chief. Firefighting was in his bones, and he embodied the spirit and passion of our department. He was passionate about organ donation, and just as he saved countless lives working out of the firehouse, he will continue to save lives in his passing,” said Kavanagh. 

An FDNY official said they are still investigating the circumstances that led to Moon’s fall.