I am working on a project which is a facililty that tests tools used in semi-conductor fabrication facilities. The spaces are clean rooms with strict control of temperature, humidity, and particulates. I am wondering, if clean rooms are considered to be "labs" under ASHRAE 90.1-2010/LEEDv4? Whether they considered labs or not will impact the Baseline system type and a number of other major inputs into the energy model. Unfortunately, I haven't been able to find a definition of "lab" in ASHRAE 90.1, the LEED reference guide, or in any of the LEED interpretations.