Zoning by Motorized Fire Damper allowing continuing work once Fire

[nattapong.s]

Hi Everyone,
I am HVAC engineer and work at tropical zone (hot and Humid) and now dealing with the fire philosophy inside substation building.

Substation is separated into 3 rooms let say A, B, C.
A = Manned Area (Control Room)
B,C = Unmanned Area (Panel Room)

Each room is provided their own individual A/C. All these rooms connected by Duct-Centralized A/C is designed each room with Fire Motorized Damper to serve the fresh air for improving indoor air quality and pressurized the substation.

It's about Zoning. Once FIRE at Room C , the Duct-Centralized will be shut down along with the Motorized Fire Damper, the individual A/C for room C also shutdown. CO2 gas suppression to be in service but the other rooms still conditioned with their own A/C.

The question is " Are there any codes applicable that allow Room A and B operating once the adjacent room is FIRE?" this is by my client request.
I feel a little bit not make any senses to me as my proposal was to shutdown all A/Cs along with the damper themselves. I spent a time acquiring in NFPA but unfortunately found nothing which request your special profession in advice, Sir.

Thanks in advance.

 

[trashcanman]

Unless you have separate return air ducts from each space, shut down everything to avoid transferring smoke to other rooms.

 

[urgross]

See NFPA 92. Place supervised smoke control dampers on the supply and return dampers as well as providing the fire dampers at rated separations. Maintain relative differential pressure for smoke control.