A compressed natural gas tank turned into a missile Monday, launching out of a Brown & Brown Chevrolet service bay, soaring more than 500 feet, crashing down through the roof of a nearby body shop and critically injuring a longtime employee.
The 41-year-old Mesa man, whose name was not released, suffered severe head injuries when the 5-gallon tank ricocheted off the body shop’s concrete floor and into him, said Mesa Fire Department deputy chief Mary Cameli. He was taken by ambulance to Scottsdale Healthcare Osborn hospital, where he was in critical condition Monday evening.
Cameli said another employee had removed the tank and placed it next to a vehicle in the north service bay of the expansive property west of Hibbert between Main Street and First Avenue. The employee had bled the tank, as is standard practice, and believed the tank was empty when he began removing the valve, Cameli said.
"The valve went one way and the tank went another direction," she said. "The tank hit the vehicle, and then shot into the air."
The man was working in the body shop, located southeast of the service bay near First Avenue, when the flying tank came through the roof about 11:30 a.m. Eight or nine other employees were in the building, Cameli said.
"As far as that tank traveled, we are very, very fortunate that more people weren’t injured," she said.
Brown & Brown managers declined comment Monday.
Employees working nearby said it sounded like an air bag had exploded.
A 5-gallon compressed natural gas tank weighs roughly 100 pounds, with pressure up to 3,600 pounds per square inch, said Mark Bumm, president of Alt Fuel Systems in Mesa. By comparison, propane tanks are up to 312 pounds per square inch and the pressure in vehicle tires is about 35 pounds per square inch.
Bumm’s company removes the compressed natural gas tanks in Mesa police squad cars as a safety precaution before the vehicles are towed to a nearby body shop.
The 50-year-old mechanic who released the valve suffered minor injuries and was treated and released, Cameli said.