As Minnesotans turn up the heat to stay warm this fall and winter, it is also important to be alert to the dangers of carbon monoxide poisoning. About 500 people die each year in the United States from exposure to carbon monoxide (CO), a odorless and colorless gas formed by the incomplete combustion of fuels.

CO is produced whenever a material burns. It can build up to life-threatening concentrations indoors when fuel-burning devices are not properly vented, operated or maintained. This includes 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.

CO dangers are most common in the winter months when a heating system malfunctions in a home or a car engine is left running in a garage. CO can also accumulate in an ice house with a gas space heater, stove or portable generator.

The Minnesota Department of Commerce offer some tips to prevent CO poisoning:

• Properly vent and maintain fuel-burning appliances. They should be vented to the outside and checked by a qualified heating contractor every year to detect potential problems. CO buildup in a home is often caused by improper venting of flue gases and may include a cracked furnace heat exchanger, blocked or undersized chimney or vents, damaged or separated vents, or insufficient combustion air supply. 
• Never use an appliance inside that is intended only for outdoor use, such as barbecue grills, camp stoves or portable generators.
• Do not idle a car in a garage, either attached or detached. Dangerously high levels of CO can accumulate even when the garage door is open.
• Know the signs of CO poisoning. Early symptoms such as headache and fatigue are similar to the flu, but without a fever. Continued CO exposure can lead to more severe headaches, dizziness, nausea, difficulty thinking clearly and fainting. If everyone in a household is experiencing symptoms, it may be CO poisoning.
• Install 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. Follow the manufacturer’s instructions for placement of your CO alarms, and pay attention to the suggested replacement date.

For more information on CO poisoning, visit the Minnesota Department of Health website, the Minnesota Commerce Department's Home Energy Guide (page 28) and the Carbon Monoxide Safety Association at www.cosafety.org.

Minnesota Energy Tips is provided twice a month by the Minnesota Department of Commerce, Division of Energy Resources. Contact the Commerce Department's Energy Information Center at energy.info@state.mn.us or 800-657-3710 with energy questions.