UPDATE 1-US CSB launches probe of Tesoro Utah refinery fire

(Adds Tesoro comment, details, CSB chairman statement)

HOUSTON, Oct 23 (Reuters) - The U.S. Chemical Safety Board was launching an investigation on Friday of a Wednesday night fire at Tesoro Corp's (TSO.N) 58,000-barrel-per-day (bpd) Salt Lake City, Utah, refinery, the board said in a statement.

CSB investigators will search for similarities between the Tesoro fire and the deadly 2005 blast at BP Plc's (BP.L) Texas City, Texas, refinery, according to the statement.

A Tesoro spokesman said the company welcomes the board's involvement into the probe of the fire.

"We welcome their participation," said Russ Jansen, spokesman for the Tesoro Salt Lake City refinery. "It's never bad to a have a second set of eyes."

The Salt Lake City Fire Department said the Tesoro blaze was caused by a leak from a flare stack, which is meant to burn off hydrocarbons refinery equipment cannot process.

The Texas City explosion began with an overflow of hydrocarbon liquid and gas from a blowdown drum, meant to disperse gases not processed in the refining process.

"These events endanger workers and the public and can disrupt the supply of needed transportation fuels," said CSB Chairman John Bresland. "A sudden release of flammable liquid from a flare or blowdown stack poses a potential risk to people, equipment and the environment and warrants a close look." (Reporting by Erwin Seba; Editing by Christian Wiessner)