(a) Each CO2 system that has a supply of more than 136 kilograms (300 pounds) of CO2, except a system that protects a tank, must have an alarm that sounds for at least 20 seconds before the CO2 is released into the space.
(b) Each audible alarm for a CO2 system must have the CO2 supply for the system as its source of power and must be in a visible location in the spaces protected.
source: CGD 73-251, 43 FR 56808, Dec. 4, 1978, unless otherwise noted.
cite as: 46 CFR 108.445