In air testing air pumps collect air samples by pulling a known volume of air through a collection device. The spores settle on the device which traps them for counting under a microscope. Mold spores are tiny and can spread easily through the air. Air sampling always includes sampling from the inside and the outside. The building should not have mold that is absent outside, and there should not be higher concentrations of mold inside the building compared to outside. Mold spores in the air vary with the cycle of the mold, atmospheric conditions and ventilation.
Specifically, spore counts for each spore category and total spore count per cubic meter are in air sample reports.