Carbon monoxide is a highly toxic gas, which is made more dangerous by the fact that it has no odor. Because it has no color, odor or taste or distinct symptoms, many people tragically fail to notice its presence until the effects become lethal. It is also a common hazard in residential homes, as it is created by fuel that has not burned completely. Heaters, dryers, ovens and fireplaces are all common sources of carbon monoxide. For this reason, a carbon monoxide detector is an essential component of any security system. There are several types of detectors, all of which contain a sensor to detect even tiny amounts of carbon monoxide. The sensor triggers an alarm to alert residents. In many locations, the law requires carbon monoxide detectors in every residence. Your security company may include the installation and monitoring of detectors in its security packages or you may obtain one on your own.