Do non-regularly occupied spaces have to be air tested?

LEED 2009 EQ 3.2 Option 2 does not identify the kinds of spaces to be tested only that one test series be done for each separately ventilated space. This can be very confusing depending on the configuration of your HVAC system. If you have many fan-coil (VAV) units with separate thermostats then you might assume each area served by these must be sampled. I disagree and have not followed that line of thinking because it would result in far too many samples and be cost prohibitive. I try to identify the areas served by individual outdoor air intakes. LEED says each area sampled cannot exceed 25,000 square feet. If an area served by a single HVAC system (outdoor air intake) is more than 25,000 sf then two samples would be collected in that area. The other things that LEED states are that the outdoor air must be set at minimum and the sampling should be done in the least ventilated areas of the area being sampled. Regarding your question, I would not sample the areas you identified simply because they are not representative of what occupants will typically experience. If the building is too complicated regarding its HVAC system to figure out what separately ventilated areas means, then I would just use the one sample set per 25,000 sf rule-of-thumb. As someone whose Masters Thesis was on IAQ and has been doing IAQ consulting for more than 25 years I find the LEED air testing requirements inappropriate for their stated goal. Unfortunately LEED V4 is going to make them near impossible to accomplish as written with them remaining of little value.