Electrical Explosion in Boiler Room Causes Power Outage at St. John’s : Hospital: Unexplained blast at medical center injures no one. Lack of power leaves patients without air conditioning for hours.

An electrical explosion in the boiler room at St. John’s Regional Medical Center in Oxnard Wednesday forced the hospital onto emergency power, darkened patients’ rooms and caused cancellation of all non-emergency surgeries.

No one was injured in the 9:11 a.m. blast that sent smoke streaming into the air at the new northeast Oxnard facility. The loud boom it created was not discernible in patients’ rooms situated in another building on the large medical campus, said Rita Schumacher, a hospital spokeswoman.

“Other hospitals have called and offered assistance, but we’re still taking emergencies,” she said. “They are just being rerouted to the outpatient surgery building.”

Some of the eight patients scheduled for surgery Wednesday were transferred about six miles to St. John’s Pleasant Valley Hospital in Camarillo, and others were rescheduled for today. But none of the 150 patients was evacuated, Schumacher said.

Workers from Southern California Edison, which supplies power to the hospital, and a private contractor, Taft Electric, were expected to work through Wednesday night to try to repair damage and restore the hospital power source, said Mike Montoya, area manager for Edison.

But by Wednesday afternoon, no cause for the explosion had been determined.

“It was a fault in their main panel,” Montoya said. “It could have been a hot wire that touched another metal object, a hot lead that went to ground, or a number of things. They will have to investigate that.”

The explosion occurred in the central plant, which is the terminal for all Edison power that comes into the facility, which opened in October, 1992. From there, the power is distributed throughout the facility.

The incident began when maintenance workers noticed smoke coming from the plant, said Capt. Ray Shaw of the Oxnard Fire Department. Soon afterward, there was an arc of electricity and a large flash.

“It had a pretty good bang, so it shook the (boiler) room a little and created quite a bit of smoke,” he said. Although there was no fire, the force blew a wind turbine off the top of the building, allowing smoke to stream into the air, Shaw said.

The emergency power generators kicked in seconds after the explosion, providing lighting in critical areas and keeping all necessary parts of the hospital functioning, Schumacher said.

But the power outage left patients without air conditioning for part of the hot day and with no television to entertain them. But workers managed to hook up air conditioning to the emergency power generators and the hospital was cooling off by the afternoon.

“We spent a lot of our time today just informing patients about what was going on,” said Vickie Lemmon, a nurse at St. John’s. “Some patients just worried that they would have to be evacuated.”

Without normal power, the kitchen switched gears as well, serving patients sandwiches and salads instead of normal fare such as roast beef and mashed potatoes, Lemmon said.

As evening fell, hospital nurses and administrators were visiting patients’ rooms and searching for a means to supplement the dim emergency lights, Schumacher said.

“We’re thinking of battery-powered lanterns,” she said. “We’re exploring all the options.”

Times staff writer Christina Lima contributed to this report.