Signal, Carbon Monoxide Alarm : A signal indicating a concentration of carbon monoxide at or above the alarm threshold that could pose a risk to the life safety of the occupants and that requires immediate action
NFPA 720 Standard for the Installation of Carbon Monoxide (CO) Detection and Warning Equipment, 2009 ed. (Std: Instll of CO Detn and Warning Equip - Amer) {343 NFC}