Should a forced air unit heating system be on or off when doing air sampling for mold, using spore traps? If the FAU has been in use is there a timeframe prior to doing the air sampling that the FAU should be off? I would appreciate any information regarding this.
Try asking in the Ancillary section. I would be interested in the responses.
Most sampling protocols state that the home should be in “normal operating conditions”. That is, if the windows are open when you arrive, they stay open. If the heat or a/c is on, they stay on. You show up and take the samples without changing the conditions. Obviously this runs in contrast to other environmental sampling ie: radon, etc. However, because of the ubiquitous nature of mold spores, its more or less a snap shot, and not a worst case sampling.
What sampling protocol are you talking about??? There should be no windows or doors left open 24 hours before testing. You will be able to tell if they were because there will be some spores only found outside in your inside samples. I myself leave the heating and cooling sytem on but test within a few feet of a return vent. Do not test close to a supply vent. Make sure all fans and air purifiers or shut off though. The less air movement the better. If some reason the this can not be avoided, reduce your sampling time. The longer you can run your pump without overloading your cartidge, the better more accurate your results. Stay away from labs with low detection limits. They are not taking enough time under the microscope.