COdetectors

Carbon monoxide detectors are safety devices that sense carbon monoxide, a colorless, odorless gas produced by incomplete combustion from fuels such as natural gas, propane, wood, oil, and gasoline. They are designed to alert occupants to dangerous CO levels so they can evacuate and seek fresh air and emergency assistance.

Most detectors use an electrochemical sensor that produces an electrical signal proportional to the CO concentration; when levels reach the alarm threshold, the device sounds an audible alert and may display a reading. Some older or lower-cost models use alternative sensor technologies. Modern detectors often include features such as digital readouts, battery backup, and the ability to interconnect with other units so that an alarm on one unit triggers all connected detectors.

Detectors are available as standalone battery-powered units or hardwired mains-powered units with battery backup, and many models can interconnect for layered protection. They are typically tested and certified to standards such as UL 2034, with guidelines from organizations like NFPA that inform recommended installation and replacement practices. Replacement intervals vary by model, but many detectors are designed to be replaced every 5 to 7 years, with some sealed 10-year units indicating end-of-life on the device.

Placement and usage guidelines emphasize coverage and reliability. Install detectors on every level of the home and outside sleeping areas. Mount on a wall 5 to 6 inches below the ceiling or on the ceiling where permitted by the manufacturer. Avoid kitchens, bathrooms, garages, and areas with high humidity or near fuel-burning appliances to minimize nuisance alarms.

Maintenance involves monthly testing, periodic sensor or battery replacement, and cleaning to remove dust. If an alarm sounds, occupants should evacuate, call emergency services if CO exposure is suspected, and ventilate the area before reentry.