Baseline Fan Power for ECM

Hi, I’m currently working on a pharmaceutical facility in Mexico where unregulated procces loads account for more tan 60% of the energy consumption. A major part of this load is due to some fans in conditioned areas but not interlocked to the HVAC system. They do not work in conjuntion but they do operate in the same room. This fans do not exhaust nor supply air into the room, they just create a loop of air filtration. We are aware that we will have to go under an ECM in order to claim savings from this fans, but we are not sure of how to establish the baseline fan power. Are we allowed to establish fan power based on paragraph G3.1.2.9 System Fan Power from ASHRAE 90.1 2007? Or shall we establish this fan power based on regular practices of local facilities? Additionally, we are claiming credit from exhaust fans that they do are interlocked with the project’s AHU’s , as they are connected through several air flow, pressure and humidity sensors.