Where should carbon monoxide alarms be installed?
Place a CO alarm outside each separate sleeping area near the bedrooms, plus inside any bedroom that contains a fuel-burning appliance (IRC R315.3, 2015 edition).
Carbon monoxide alarms must be located outside each separate sleeping area in the immediate vicinity of the bedrooms - typically in the hallway that serves the bedrooms. (This is the Location rule, Section R315.3 in the 2015 IRC.)
If a fuel-burning appliance is located inside a bedroom or its attached bathroom, a CO alarm is also required within that bedroom.
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