Fatal Refinery Fire Blamed on Vapor Cloud
Charred towers and a burned out work areas (lower center) are shown at a Tesoro Corp. refinery, Friday, April 2, 2010, in Anacortes, Wash. An overnight fire and explosion at the refinery killed four people and critically injured three others who were work
Houston Chronicle via YellowBrix
April 06, 2010
ANACORTES, WA – The deadliest refinery accident since 2005 was described Monday as “more of a fireball than an explosion” but is not yet prompting a federally requested shutdown of the plant.
A vapor cloud of hydrocarbons ignited within seconds, killing or burning seven Tesoro employees who were working about 50 feet from a unit used to make high-octane fuel, said Robert Hall, lead investigator with the U.S. Chemical Safety and Hazard Investigation Board.
Although residents near Tesoro’s plant in Anacortes, Wash., said they felt windows shake, the actual scene itself doesn’t show significant blast damage, Hall said.
The fire at the refinery’s naphtha unit killed five employees of San Antonio-based refiner Tesoro. Two remain hospitalized for burns and are in intensive care. One remains in critical condition and the other’s condition has been upgraded from critical to serious, a hospital spokeswoman said.
The CSB sometimes makes urgent recommendations that may include a request that a plant close for a time, but it isn’t making that request of Tesoro now, Hall said.
CSB spokesman Daniel Horowitz said that after the BP disaster in Texas City many people outside the industry recognized that the safety of this sector needs to improve.
The CSB oversees 150 refineries in the United States and thousands of chemical plants, but about half of its outstanding investigations are of accidents at refineries, officials said.
The accident is the worst since 15 workers were killed and more than 100 injured at BP’s Texas City refinery in 2005.
The area where Friday’s Tesoro accident occurred was extensively burned, but had a relatively small footprint, only half the size of a football field, compared to the Texas City explosion, Hall said.
While Tesoro was not yet asked to stop work at the plant, Horowitz said there is precedent set by the Silver Eagle Refinery accident in Woods Cross, Utah, which damaged more than 100 houses near the plant on Nov. 4. In that accident, a 10-inch pipe failed, releasing gas that ignited, creating a fireball.
After the Silver Eagle accident, Horowitz said the CSB “took the unprecedented step of asking the plant to shut down temporarily because it didn’t have safeguards in place. The plant’s management did agree to shut the refinery for a time.
The CSB still has an active investigation of an accident at Tesoro’s Salt Lake City refinery that occurred on Oct. 22. That accident “had similarities” to the 2005 BP explosion, Horowitz said, “in that there was a liquid released from a flare stack onto the ground. It ignited and there was a big pool fire on the ground.”
The CSB investigation is expected to take about 18 months to complete, Hall said. The CSB is an independent federal agency that investigates major industrial accidents.
In the meantime, Tesoro shares dropped, with a Deutsche Bank analyst on Monday downgraded Tesoro’s shares to hold from buy.
The company’s shares fell 78 cents, or 5.4 percent, to close at $13.61 Monday in New York Stock Exchange trading.