Other detectors have a color sensor which can be evaluated by trained technicians to determine the CO level. Detectors listed by UL are required to sound only at levels above generally accepted safety standards. Low levels, which can cause chronic health problems, must be measured using professional instruments. Read and follow all instructions. In general, most detectors should be vacuumed at least twice a year, and tested every week.
Most detectors have a test button which is pressed until a loud alarm sounds.
If the detector fails to test properly, have it repaired or replaced immediately. Carbon monoxide detectors save lives and prevent serious health side affects. Make sure your home and family is protected with a relatively small investment in at least one CO detector. For more information request other notes in the Carbon Monoxide series.