JACKSONVILLE, Fla. -

An electrical worker suffered serious burns in an electrical discharge at Advanced Disposal's headquarters on the Westside on Tuesday morning.

The 29-year-old man was taken to UF Health Jacksonville with life-threatening injuries.

The Jacksonville Sheriff's Office said the industrial accident occurred about 7:40 a.m. when contractors for Pilot Electric were working on a piece of equipment at the residential garbage pickup facility on Normandy Boulevard.

While the workers believed the power was off, it was not, and two men were shocked. The 29-year-old man's clothes caught fire.

He was taken to UF Health Jacksonville, then flown to the burn center at UF Heath in Gainesville. The other man's hair was singed but he was OK and not transported to a hospital.

Advanced Disposal said the two men work for Pilot Electrical, which had personnel on site for an electrical project.

"At this point in time, it appears that this was just a horrible accident," Sgt. Jay Farhat said. "We are not exactly sure why the electricity was not turned off. We are conducting that investigation now. We have also contacted (the Occupational Safety and Health Administration) and they are conducting their own investigation to determine the cause of the accident."

"Advanced Disposal staff acted immediately by extinguishing the fire with a fire extinguisher and calling 911," officials said in a news release. "Their immediate and life-saving actions were heroic."

Advanced Disposal said it is working with JSO and Fire-Rescue as they complete their investigation.

Solid waste and recycling collection operations serviced from this facility were not affected by this incident, officials said.