A carbon monoxide detector senses carbon monoxide in the air and sets off either a high-pitched alarm or, in some detectors, a loud voice warning to let the household know that a leak exists. They work in much the same way as smoke detectors, and some units are actually combination smoke and carbon monoxide detectors.
The Centers for Disease Control and Prevention estimates that about 20,000 people are treated in emergency departments for carbon monoxide poisoning each year, and more than 4,000 cases each year are serious enough to require hospitalization. Around 400 deaths result from carbon monoxide poisoning every year. According to carbonmonoxide-poisoning.com, it is likely that more than half of poisoning deaths worldwide come from carbon monoxide.
Carbon monoxide is produced by propane-fueled heaters and equipment, defective furnaces, wood-burning stoves, portable generators, and during house fires, among other household sources. Carbon monoxide poisoning can also result from car engines if there's no ventilation--for instance, leaving a car running in the garage with the garage door shut.
One of the most dangerous features of carbon monoxide poisoning is that people usually don't know that it's happening. Symptoms include fatigue, feeling lightheaded, nausea and disorientation, which are symptoms that can be mistaken for the flu, among other things. If a person feels unwell and decides to just lie down and get some rest, serious illness or death can result. Sometimes, the damage from carbon monoxide poisoning can show up more than a month later as neurological problems.
Carbon monoxide detectors are widely available and easy to install. Some models just plug into a wall outlet, requiring electricity, and others mount to the ceiling and run on batteries. Carbon monoxide detectors can be purchased alone or as a combination smoke and carbon monoxide detector. There should be at least one unit on every floor of the house. If using a battery-operated detector, remember to test the unit regularly and replace the battery at least once a year, or more often if the manufacturer recommends it.