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As temperatures fall, carbon monoxide dangers rise

10/24/2016 10:49:44 AM

With the start of the fall and winter heating season, the Minnesota Commerce Department urges Minnesotans to be aware of the risks of carbon monoxide poisoning.

Each year about 500 people die in the United States from unintentional exposure to carbon monoxide (CO) – a silent, odorless, colorless gas formed by the incomplete combustion of fuels.

Dangerous concentrations of CO can build up indoors when fuel-burning devices are not properly vented, operated or maintained. These include furnaces, water heaters, gas or kerosene space heaters, gas boilers, gas ranges and ovens, gas dryers, charcoal or gas grills, fireplaces and wood stoves, motor vehicles and yard equipment.

The risk of deadly CO poisoning is greatest in the winter months, when a heating system may malfunction in a home or a car engine is left running in a garage.

People can also be exposed to high CO levels while camping, fishing, hunting or boating. For example, concentrated CO can form in the cabin areas of boats or in ice houses with portable heating equipment.

Here are three basic tips to prevent CO poisoning:

Properly vent and maintain fuel-burning appliances

All fuel-burning appliances should be vented to the outside and should be checked by a qualified heating contractor every year to detect potential problems.

CO buildup in a home often results from problems with venting flue gases. Causes may include a cracked furnace heat exchanger, blocked or undersized chimney or vents, damaged or separated vents, or insufficient combustion air supply.

An appliance intended for outdoor use such as a barbecue grill, camp stove or portable generator should never be used in an enclosed space. Do not idle a car in a garage, either attached or unattached, for any length of time. Dangerously high CO levels can accumulate even if the garage door is open.

Know the effects of CO poisoning

When CO is inhaled into the lungs, it displaces the oxygen in the blood stream and affects all major organs and muscles. Breathing in high levels of CO can cause people to lose consciousness and die even before they are aware of any symptoms.

CO exposure can produce flu-like symptoms. The first signs may include mild headache and breathlessness with moderate exercise. Continued exposure can lead to more severe headaches, dizziness, fatigue and nausea.

Some ways to distinguish CO poisoning from the flu:

  • You feel better when you are away from home.
  • Everyone in the home is sick at the same time.
  • Family members most affected spend the most time at home.
  • You don’t have a fever or body aches that come with the flu.

Install and maintain CO alarms in your home

Minnesota law requires that every home have at least one operational CO alarm within 10 feet of every room used for sleeping. All CO alarms should conform to the latest Underwriters Laboratory (UL) standards. Follow the manufacturer’s instructions for installation of your CO alarms and note suggested replacement dates.

For more information on CO poisoning, visit the Minnesota Department of Health website, the Minnesota Commerce Department’s Home Energy Guide (page 28) or the Carbon Monoxide Safety Association at

Minnesota Energy Tips is provided twice a month by the Minnesota Department of Commerce, Division of Energy Resources. Contact the Department’s Energy Information Center at or 800-657-3710 with your energy questions.


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