MISSISSIPPI STATE -- Winter's chill sends people scurrying for the thermostats and space heaters to stay warm, but these comfort items can turn deadly if not operating properly.

Nearly every winter brings stories of individuals or families killed or sickened by overnight carbon monoxide poisoning in closed spaces. In these situations, even those who attempt to rescue them can become ill or die unless the area is ventilated before they enter.

Victims can survive if they are removed from the area soon enough. Some require hospitalization while they are given oxygen as their body recuperates.

Herb Willcutt, safety specialist with Mississippi State University's Extension Service, said carbon monoxide, the odorless, tasteless product of incompletely burned fuel, displaces oxygen in the body and can kill.

"Carbon monoxide can be produced by such things as a burning candle, a gas or kerosene space heater not properly maintained or operated, automobile exhaust in an enclosed area or a smoldering wood fire," Willcutt said.

When inhaled, carbon monoxide combines with the blood's hemoglobin and displaces the oxygen that normally would be carried. Carbon monoxide does not release quickly, and a high concentration of carbon monoxide in the blood starves the body's tissues of oxygen.

Willcutt said low levels of carbon monoxide concentration in an enclosed area cause drowsiness, headaches, nausea and fatigue in those exposed. After a longer or more concentrated exposure, the skin turns cherry red and victims suffer a violent headache. Breathing carbon monoxide for longer periods can lead to unconsciousness, irreversible damage or death.

"The fact that it does not have odor, taste or visible qualities allows it to become concentrated without detection in areas that are not ventilated," Willcutt said. "When a space heater or other source is producing carbon monoxide in a confined area, occupants may be exposed to gradually increasing amounts and not notice symptoms before it's too late."

To avoid carbon monoxide poisoning, maintain heating equipment correctly and have a qualified technician inspect, clean and adjust units annually.

Another way to prevent carbon monoxide poisoning is to avoid supplemental open flame heaters such as those that burn kerosene, propane or natural gas that are not designed for use in confined spaces. Never allow a vehicle to run in a closed garage even briefly.

As a further precaution, Willcutt recommended installing carbon monoxide detectors throughout homes and living areas. These cost between $12 and $20 and are available at hardware and general merchandise stores.