Sinclair Oil Corp. says the flash fire happened Tuesday inside a gas recovery unit at its refinery, about five miles east of Rawlins.
The Rawlins Daily Times reports Tim Bjork, Eric Hansen and another unidentified worker were critically injured and being treated at a burn center in Greeley, Colo. A fourth worker was treated and released from Memorial Hospital of Carbon County.
The federal Occupational Safety and Health Administration has sent two investigators to the facility to look into the incident.
Salt Lake City-based Sinclair says there appeared to be little or no damage to the facility.
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