Testing of a building for mold typically involves both air and surface sampling. Surface sampling involves collecting a sample of material suspected of harboring mold with a sterile swab or tape. This sample is then viewed under a microscope to determine if the sample contains mold, and if so, what type of mold. Air sampling involves collecting a known volume of air and determining the number and types of mold spores present. Indoor levels are then compared to outdoor levels to determine if mold amplification is occurring within a building. Mold levels indoors should generally be 30-70% those of outdoor levels. If they are higher, then there is a mold problem.
