Carbon Monoxide Alarms
Carbon monoxide alarms are designed in the
style of smoke alarms: when the carbon monoxide level increases above a threshold
level, the alarm sounds. Exposure limits for industry are regulated by OSHA, and
currently specify a maximum concentration of 50 ppm. Residential exposure limits
are less clear. Home CO detectors generally sound an alarm within 15 minutes when
CO is 400 ppm, with increasingly longer delays to alarm, up to 8 hours when CO is
Other important issues in evaluating the
efficacy of CO alarms include the sensitivity and specificity of the alarm and the
(often automatic) calibration of the instrument.
At this time, no studies exist examining
the efficacy of carbon monoxide alarms.