ASHRAE 62.1 allows for air to be moved from one indoor space to another (transfer air) as long as the space air is transferred from is of equal or lower classification than the space it is transferred into (meaning quality of air with class 1 being cleanest and class 4 being most contaminated).
On a project, we are using transfer air to supply small 2-person meeting rooms. Air is mechanically extracted from these meeting rooms and replaced with transfer air from the adjacent corridor space through high-level grills and ductwork connection. The corridor space has a dedicated fresh air supply from a central AHU.
This scenario, while clearly allowed in the standard, does not seem to fit the calculator unless we account for the corridor and meeting rooms as a single zone.
Does anyone know/ have experience of how to document this scenario in the Minimum Indoor Air Quality Performance Calculator? Any advice would be really appreciated.