AHUs not within tenant space

The answer is definitely YES, but I'm struggling to figure out how to do that. I just received a clarification request from my design submission regarding this. We have a central air handler serving the entire building, including 9 zones within my boundary. I had used the sum of the design CFM ranges of my various VAVs, but they want me to either do the calcs for all spaces in the building (aint happenin), or they allow the following: "it is acceptable to use a fraction of the total supply air from the central air handling units as long as the information regarding the amount of air allocated to the project versus the other spaces is provided." I can easily calculate this based on sf ratios, but how do I put that into the form? Do I just plug that CFM into the last line of the form (Project Design Outdoor Airflow) after multiplying it by my known OA%?

It is based on supply air, not square footage. If you can work out how much total air is supplied just to your space then you can use that number for your system air (Vps). Then you can use the %OA to determine your design outdoor air. This is not really something you can show in your calculator so you will have to submit a mechanical plan and narrative explaining where the numbers are coming from.