To limit the probability that, during a failure of the normal power supply to a fire alarm system, the fire alarm system will not be capable of performing its intended functions for a length of time sufficient for normal power to be restored, which could lead to:
To limit the probability that, during a failure of the normal power supply to a fire alarm system in a fire situation, the fire alarm system will not be capable of performing its intended functions for a length of time sufficient for persons to evacuate or move to a safe place, which could lead to persons not being promptly notified of the fire, which could lead to delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons.