Shakopee, MN – A 61-year-old Credit River Township man was transported to Hennepin County Medical Center (HCMC) in Minneapolis on Jan. 30 after he was exposed to elevated levels of carbon monoxide in his garage.

The man was using a gas power washer for about two hours to clean the inside of the garage, while the doors were partially closed, Fire Chief Doug Hartman said. The carbon monoxide seeped into a walk-in closet, which shared a wall with the garage, causing a woman who was in the basement of the home to also feel the ill effects of the gas, but she was not transported, he said.

When people may have been exposed to elevated levels of carbon monoxide, medics transport them to HCMC for testing, because if poisoning is detected, HCMC has hyperbaric chambers for treatment, Hartman said.

It is unclear in this case if the man needed to be treated in the hyperbaric chambers, Hartman said.

Carbon monoxide is a colorless and odorless gas that can accumulate in the blood and deplete it of the ability to carry oxygen, according to the U.S. Consumer Product Safety Commission. At sustained concentrations above 150 to 200 parts per million, it can cause disorientation, unconsciousness and death.

When firefighters arrived at the home in the 8000 block of Covered Bridge Road, the carbon monoxide reading was about 40 parts per million, a level where a person would feel ill effects – similar to flu symptoms including nausea, rosy cheeks, headaches and shortness of breath – after about eight hours of exposure, Hartman said.

This incident nearly went unnoticed, albeit not as the result of a faulty detector or dead batteries.

Firefighters were paged to the home by an alarm company that reported a carbon monoxide alarm twice – once at 5:02 p.m. and a second time about five minutes later – but were canceled by the homeowner both times, as he stated he was at home and it was a false alarm, Hartman said.

But given the back-to-back calls by the alarm company, Hartman decided to respond to the home to check for carbon monoxide levels and verify that it was indeed a false alarm.

While on a routine response to the home, which means lights and sirens are not used, Hartman contacted Scott County dispatch and asked for the homeowner’s phone number. When the fire chief called the home, there was no answer.

Hartman then reported that information back to dispatch and requested they place a call to the homeowner, which also resulted in no answer.

Hartman stepped up his response to a code three, which indicates the use of lights and sirens, because he had “a gut feeling that something wasn’t right,” he said.

But shortly before Hartman arrived, the homeowner called dispatch and stated he was in the garage and didn’t hear the phone, but everyone was OK, Hartman said.

Hartman once again slowed his response, but continued to the scene.

When Hartman arrived on the scene, the man stated he was light-headed and had tightness in his chest, which are symptoms of carbon monoxide poisoning. The fire chief monitored the man’s vital signs, called Allina and started a fire engine with a crew to the home.

It was then that firefighters located the woman whose cheeks were “as red as roses” and stated she had a headache, which are also signs of exposure to elevated levels of carbon monoxide, Hartman said. So he advised the homeowners to take their three large dogs and go outside before the man was transported to the hospital.

The dangers of carbon monoxide are real, Hartman said. It is important that people remember to replace the batteries in carbon monoxide detectors at least twice a year – and replace the detector every five years.

Small gas engines emit a tremendous amount of carbon monoxide, so it is important not to run them inside the garage, Hartman said. Firefighters also respond to several carbon monoxide calls a year after a vehicle is left running inside a garage and the wind blows the gas into the home.

Hartman also suggests making sure vents to household appliances and furnaces are clear of snow, which can also cause carbon monoxide to get sucked back into the home.