An explosion at the United Technologies Corp./Pratt and Whitney
plant on Metcalf Road northeast of Morgan Hill Thursday evening
destroyed one building, sent a mushroom-like plume of white smoke
into the air and ignited a grass fire.
An explosion at the United Technologies Corp./Pratt and Whitney plant on Metcalf Road northeast of Morgan Hill Thursday evening destroyed one building, sent a mushroom-like plume of white smoke into the air and ignited a grass fire.
Only one injury was reported – a worker with hearing damage.
“The three story building was completely destroyed,” said Annie Vandergoot, a dispatcher with the California Department of Forestry and Fire Protection in Morgan Hill. “Only the metal skeleton was left, in the middle of a large debris field.”
Early reports that ammonium chloride was released into the air were incorrect.
Workers were mixing solid rocket fuel in a building set apart from the main campus of the south San Jose facility when the structure blew up and burned at 5:52 p.m.
“The five operators were not in the actual building but in a nearby bunker about a half mile away,” said Julie Anderson, manager of communications for the company. The fact that they were in the bunker absolutely prevented further injury or loss of life, she said.
Firefighters, command staff and emergency medical personnel from CDF and San Jose Fire Department converged on the site to battle a grass fire that started from the explosion, eventually burning 20 acres at the rural Coyote Valley site.
Santa Clara County Fire Department provided its hazardous protection agency. UTC also has its own onsite fire fighting team. The grass fire was controlled by 8:30 p.m.
UTC/Pratt Whitney manufactures rocket motors for Department of Defense missiles and for NASA’s space shuttles.
Anderson said there was a release of chemicals into the air but that it was the normal result of testing.
“What was released was a pretty standard ingredient,” she said. “We conduct rocket motor firings and (the release) was nothing more than would be in the air during a normal test – fuel, oxidizers and binders.”
Webb Harwell, manager of business development at the plant, explained further.
“You have a burning operation,” he said. “The primary ingredients are carbon dioxide, aluminum oxides, small amounts of chlorides and of ammonium.”
Harwell said the five operators are back at work but will receive crisis counseling today.
“We’ll all get back to work today,” he said.
Anderson said this is the first time in 40 years that UTC has had an explosion of this type, from mixing rocket fuel. She said UTC is putting together an investigation review board.
“We need to figure out the cause of ignition,” she said.
The explosion could be heard for miles and the plume of smoke seen even further.
