To limit the probability that fuel supplies to emergency power systems will not be maintained in the event that fuel supplies to other systems are required to be shut off, which could lead to the inability of the emergency power systems to supply emergency lighting systems to illuminate floor areas and egress routes, which could lead to safety hazards [bumping, tripping, falling, etc.], which could lead to harm to persons.
To limit the probability that fuel supplies to emergency power systems will not be maintained in the event that fuel supplies to other systems are required to be shut off, which could lead to the inability of the emergency power systems to supply emergency systems, which could lead to the inability of:
This is to limit the probability of harm to persons.