A blocked heating vent raised carbon monoxide levels at a Parkville retirement community yesterday morning, sending three workers to Maryland Shock Trauma Center and prompting the evacuation of several hundred residents, Baltimore County fire officials said.
No residents were injured, but two maintenance workers at Oak Crest Village and a housekeeper reported symptoms consistent with carbon monoxide poisoning several hours after the evacuations, said Capt. Glenn A. Blackwell, a Fire Department spokesman.
The three employees were treated in a hyperbaric chamber, which is used to clear carbon monoxide from the bloodstream, Blackwell said.
They were in good condition and were expected to be released last night, said Mark Erickson, executive director of Oak Crest.
Firefighters were called to Oak Crest, a 100-acre complex in the in the 8800 block of Walther Blvd., about 7:25 a.m. after a detector sounded in an electrical room. Carbon monoxide was measured at two times the level at which firefighters find cause for concern, Blackwell said.
It appears the poisonous gas built up in Renaissance Gardens Terrace -- an assisted-living facility -- when a piece of insulation fell and blocked a boiler exhaust vent, Erickson said.
Crews immediately evacuated 120 residents to a nearby community building, where they were served breakfast while firefighters ventilated the building and tested the air. Firefighters also began evacuating about 300 residents from two other residential buildings that use the same heating system.
Blackwell said as soon as crews started to ventilate those two buildings, the carbon monoxide level dropped and residents were allowed to return to their apartments within an hour. The problem was corrected in all three buildings within about three hours, he said.
All residents were checked by medical staff and were found to have suffered no ill effects, said Erickson. The three employees reported their symptoms about 2 p.m., and the rest of the staff was checked as a precaution, he said.
Carbon monoxide, which is colorless and odorless, rapidly starves the body of oxygen. Early symptoms include headache, fatigue, confusion, nausea and dizziness. At high levels, it causes convulsions and seizures that can lead to coma or heart attack.
Erickson said Oak Crest is in the process of connecting carbon monoxide detectors to its central fire alarm system. About 2,200 people age 65 and older live at the complex, which includes 15 residential buildings and three community centers.