Authorities say 12 workers were hurt when a steam pipe burst at the University of Utah and sprayed scalding water on subcontractors in an underground utility vault.

Fire Capt. Michael Harp told The Associated Press the men were blasted by 380-degree steam that erupted from the end of a pipe opened Monday during upgrade work.

University spokesman Remi Barron says nine of the workers were hospitalized at a burn unit across campus. Three were in critical condition, but Barron says they're expected to survive.

Three others were taken to Salt Lake Regional Hospital.

The accident happened inside a vault about 100 yards from a co-generation plant that produces electricity and steam for campus buildings.

Harp said no students or passers-by were endangered because the area is fenced off.