Dear All,

For a LEED project we are modeling a research laboratory building where
in the proposed case most of the lab spaces are provided with 6 ACH
during occupied and 2 ACH during unoccupied periods for health and
safety reasons.

I am assuming that the corresponding HVAC system for these spaces would
be defined by G3.1.1 Exception d and that separate HVAC systems shall be
provided for each laboratory space with more than 5000 CFM exhaust.

Assuming my approach is correct, the question is how to model this in
eQuest? We are inputting ACH values at zone level. Is there a way of
dynamically adjusting these ACH values on an hourly basis (ie.
schedule?). When G3.1.1 Exception d requires that exhaust and make-up
air volume be reduced to 50% of design values during unoccupied periods,
is the correct approach to provide 6 ACH (=proposed flow rate) during
occupied and 3 ACH during unoccupied periods?

Thank you for any responses,

Omer Moltay, LEED AP BD+C, ASHRAE BEMP