Normal power electrical room is built inside emergency generator room

[anbm]

NFPA 110 requires emergency generator room have 2-hour fire rated wall and no other equipment can be installed in this room except emergency system distribution equipment.

Can a separate / small electrical room built inside emergency generator room for normal power panels? This normal power elec. room will have 1 hour fire rated wall. The outside / larger emergency generator room still have 2 hour fire rated wall.

 

[petersonra]

NFPA 110 requires emergency generator room have 2-hour fire rated wall and no other equipment can be installed in this room except emergency system distribution equipment.

Can a separate / small electrical room built inside emergency generator room for normal power panels? This normal power elec. room will have 1 hour fire rated wall. The outside / larger emergency generator room still have 2 hour fire rated wall.

I suspect if the smaller room also had two hour fire walls it would be considered as a separate room. You could make sure it would be so considered if it had a door that did not open into the emergency room.

 

[charlie b]

NFPA 110 requires emergency generator room have 2-hour fire rated wall and no other equipment can be installed in this room except emergency system distribution equipment.

I don't have time to look this up right now. But I am fairly certain it is not the generator that must have a separate room. I think the rule applies to the transfer switch and the distribution panel. Can anyone confirm or refute?

 

[anbm]

I don't have time to look this up right now. But I am fairly certain it is not the generator that must have a separate room. I think the rule applies to the transfer switch and the distribution panel. Can anyone confirm or refute?

NFPA-110

3.3.3* Emergency Power Supply (EPS). The source of electric power of the required capacity and quality for an emergency power supply system (EPSS).

3.3.4* Emergency Power Supply System (EPSS). A complete functioning EPS system coupled to a system of conductors, disconnecting means and overcurrent protective devices, transfer switches, and all control, supervisory, and support devices up to and including the load terminals of the transfer equipment needed for the system to operate as a safe and reliable source of electric power.


7.2 Location.

7.2.1 Indoor EPS Installations. The EPS shall be installed in a separate room for Level 1 installations.

7.2.1.1 The EPS room shall be separated from the rest of the building by construction with a 2-hour fire resistance rating.

7.2.1.2 EPSS equipment shall be permitted to be installed in the EPS room.

7.2.1.3 No other equipment, including architectural appurtenances, except those that serve this space, shall be permitted in the EPS room.