Are you referencing what is called an "Area of Refuge"? That is in ANSI ADA (Americans with Disabilities), and is a 'safe' area for handicapped individuals to await rescue. It is usually within a rated staircase, on each landing, and out of the egress path of the non-handicapped occupants. Dimensional requirements are within the ANSI code, as adopted within your state/area.
It is the Emermency Power Systems in NFPA-110 section 7.2.2.
The EPSS equipment shall not be installed in the same room with the normal service equipment where the service equipment is rated over 115V and is equal or greater than 1000A.
I call this room the Life Safety Room. Pretty much all of the equipment being fed from the generator that if for life safety.
