I am modeling a lab building for a LEED v4 building. I have a few questions/assumptions I was hoping could be verified.

1. The proposed design can take credit for savings associated with turning down lab exhaust airflows below 50% of design.

2. The credit taken above can be 100% OA in the baseline model.

3. What is the best way to model a constant volume with bypass damper lab exhaust fan in the proposed. I'm currently just modeling it constant volume, but have been debating building a custom curve. Has anyone gone down that rabbit hole before.

-Thanks Chuck