[chris]

Four workers at the Silver Eagle Refinery in Woods Cross, Utah, suffered severe burns the evening of Jan. 12, 2009, after a cloud of flammable vapor escaped a storage tank and ignited, touching off a fire that took most of the night to control, according to fire officials and state safety regulators.

The blaze broke out about 5:30 p.m. after operators bypassing a stabilizing unit to clear a line with nitrogen gas allowed naphtha vapor to vent from a storage tank, authorities said. The vapor drifted across the tank farm and found an ignition source, setting off a flash fire that spread as far as 230 feet.

The fire engulfed a 42,000-gallon gasoline tank. More than 80 firefighters from several nearby cities worked through the night, pumping foam into the tank vents around 9:30 p.m. to smother the flames by cutting off their oxygen supply. Crews did not put out the fire until about 4 a.m. Tuesday.

Police ordered a mandatory evacuation within a half-mile of the refinery, emptying homes along 800 West between 2100 South and 2600 South. About 100 residents took shelter at Woods Cross High School before the order was downgraded to voluntary around 8:30 p.m. Utah Transit Authority suspended commuter rail service through the area and ran buses in its place.

Two refinery operators and two contractors, identified by hospital officials as Robert Benoit, Alex Bloomfield, Phillip McSwain and Timothy Harter, were flown or driven to the burn unit at University Hospital. Harter, who fell while escaping the flames, was listed in critical condition with second and third degree burns to his face and hands. The other three were listed in serious condition.

State records showed the refinery had been cited for 23 safety violations, 13 of them serious, since 2002, and had caught fire four times since 2003 without injury. In June 2010, the Utah Occupational Safety and Health Division fined operator Silver Eagle Refining more than $1 million, including $896,000 for willful violations, citing the January fire along with a separate, larger explosion at the same refinery that November.