How sampling works
What Mold Testing in White Sulphur Springs, WV Really Measures
At its core, mold testing is about capturing spores and letting a lab count them. For air, the sampling pro attaches a sealed spore-trap cassette to a pump calibrated with a rotameter, then runs it at a set flow rate, often 15 liters per minute for 5 minutes, which pulls 75 liters of air across a sticky slide. The lab counts and identifies what landed on that strip under a microscope, then converts the count to spores per cubic meter of air.
Indoor numbers mean almost nothing on their own. Outdoor air always carries spores, which is why a control sample gets taken outside during the same visit. If indoor levels run well above outdoor levels, or the indoor sample is dominated by types like Stachybotrys or Chaetomium that rarely show up outside in any quantity, that points to an indoor source. There are no federal numeric limits for indoor spores, which is exactly why the outdoor comparison carries so much weight.
Surface sampling answers a different question: what is this stain? A tape-lift presses clear adhesive tape onto the growth, a swab works on rough or curved surfaces, and a bulk sample is a cut piece of drywall, carpet or insulation sent whole. For suspected growth inside a wall, some pros take a wall-cavity air sample through a small port. Folks in White Sulphur Springs usually call for testing to document conditions for a sale, a lease dispute or a clearance after remediation.