Where should I place a carbon monoxide detector?
Because carbon monoxide is slightly lighter than air and also because it may be found with warm, rising air, detectors should be placed on a wall about 5 feet above the floor. The detector may be placed on the ceiling.
Do not place the detector right next to or over a fireplace or flame-producing appliance. Keep the detector out of the way of pets and children.
Each floor needs a separate detector.
If you are getting a single carbon monoxide detector, place it near the sleeping area and make certain the alarm is loud enough to wake you up.