Air handling unit smoke dampers

[remp]

I have a new air handler and exhast fan serving 3 floor of production area. The air handelr is located on the top floor and serves each floor via a masonary shaft. The consultant wants smoke dampers on each floor take off so that on fire mode the air handler shuts down and the smoke dampers close. I think this is fine.

However he also wants smoke dampers on the discharge side of the air handler and on the intake of the fan to do the same. I dont know why these are required. Only 20ft away from the air handler and fan the floor smoke dampers exist and will cloe anyway. There is no take off between the air handlier and the first set of floor smoke damper. Is this a waste, can I delete them?

 

[gouveia]

Not sure what codes your area follows. Assuming that NFPA 90A is applicable it depends upon what the CFM of the unit. If over 15,000 CFM then at each story at the return in addition to downstream of the air filter.

It seems to me that the Uniform Mechanical Code is similar but I can't remember off the top of my head.

 

[ercanbaser]

I dont remember any code states to install fire dampers on discharge and intake ducts but if the hvac room is fire rated, intake fire damper can prevent the fire&smoke from outside to hvac room by intake duct and discharge fire damper can do same job from hvac room to outside. If the periphery of hvac room is not risky for fire , fire dampers are waste...

Chapter 51 Fire and Smoke Management -ASHRAE 98 may helps...