It can be a particular hazard for children, the elderly, or anybody who works in an enclosed area like welders, firefighters, car repairmen, and even toll booth operators.In workplace environments, OSHA actually sets limits on the level of allowable CO. Employers can't expose their workers to ambient air with over 35 parts-per-million of CO.

There are several types and designs of CO detectors. Some rely on sensors that cycle their own levels of CO throughout the day, making them able to detect changes in the nearby air. They also make battery-powered detectors with passive sensor technology, which is nice because it doesn't consume too much electricity to operate.

How many detectors should you have? Every dwelling should have at least one, but in our estimate, this is insufficient for a multi-storied home, or one with greater than 2,000 square feet of space. When in doubt, we would consult building codes for precise specifications.

Of course, it's important to install these correctly and avoid positioning them too closely to heat-burning sources like an oven. Otherwise, just like your smoke detector, it'll go off all the time with false positives.