One inmate and two detention officers were transported to Marcus Daly Memorial Hospital after a propane exhaust leak at the Ravalli County Detention Center.
Sheriffs say at about 1 a.m. Sunday, inmates in the west block reported symptoms including headache, nausea and burning eyes. They also noted a bad smell.
Officers moved all of the West Block inmates to the detention center library, and medical staff was called in to care for them. One inmate fell on his way to a rest room and struck his head on the floor. The inmate was transported to the hospital by ambulance.
Detention staff located a propane exhaust leak in a boiler. The boiler was shut down, and officers ventilated the facility with fresh air.
Northwest Energy came in to ensure that the carbon monoxide levels had gone down and that the facility was safe. Once this was done, inmates were moved back to their housing block, and medical staff continued to monitor their health.
Sheriff Chris Hoffman said officers responded quickly. "Had this team not acted as quickly and efficiently as they did, the outcome could have been tragic."
The county's maintenance staff also responded to the emergency and is looking into the cause of the leak.