Construction workers using welding torches caused a smoky smell to permeate LDS Hospital, putting the building on lockdown for a short time Thursday night.

Officials were called to the hospital at C Street and 8th Avenue earlier in the day because of the smell but didn't find any indication of fire. They were called back just after 5 p.m. as the odor spread.

Salt Lake City fire spokesman Scott Freitag said welders drilling through 5-inch-thick concrete on the ninth floor caused the smoke.

"They were using torches to cut through, and we believe it caught onto insulation and spread, and then the air-handling system spread the smoke smell," Freitag said. Crews put out a small fire, he said.

The hospital was on a lockdown until about 7:30 p.m. but still operating, and no one was evacuated or injured. Emergency patients were diverted to other hospitals.

Patients weren't in any danger, said LDS Hospital spokesman Jess Gomez.

— Lana Groves