Stachybotrys Found Outside

Has anyone found Stachybotrys in their exterior mold spore samples when it is not present on the interior of the home being tested? Why would it show up on the exterior sample if it’s not present inside the home?

this is not uncommon, more info needed though what stain if any in interior, also your climate area is a consideration

These kinds of anomalies should have been covered in detail in your training for IAQ sampling. I am hoping you had some kind of formal training before going out on mold testing calls. I do not do them myself for about 10,000 different reasons. Had the training several different times but made a business decision never to get into MOLD. What Dennis said is absolutely correct. This should have not been a surprise to you.

Avoid testing around any straw outside, if possible. Stachy loves to grow on straw.

They call it INDOOR air quality for a reason

Im just curious, even if we happen to test by straw and some shows up on the baseline, why are we concerned if it is not inside? Even it were outside, we are looking for elevated conditions inside, which sound like they do not exist. I would see a problem with testing by an elevated area outside which would cloud the inside numbers, but that is a rare occurance if you know what you’re doing. End of story right?

this is not uncommon to have exterior mold and no interior mold, climate conditions are a factor to be considered, the post of origin was from GA, that climate plays a roll, also just because mold is outside does not mean not to be concerned after all please remember what mold’s role is in our environment, what does it do!! it is a agent of decay!!!

Yes, you should only be concerned with the air on the inside but you should always avoid anything that will give you a false reading outside.
Another example is avoid testing under tress. Why, you ask? Because trees can put out excessive Aspergillus/Penicillium spores thus screwing up your ten times the outside ratio, used to determine indoor toxicity levels. The outside Aspergillus/Penicillium spores will most likely look different under a microscope, but is your lab going to caught it? More than likely they do not even care to.
Going back to the Stachy count outside, it will just confuse things if you have a Stachy count outside. It is very hard to explain to a customer, why he should be concerned about the one Stachy spore inside (confined area) when there is one Stachy spore outside (open area).
Just be careful how you take your samples and problems like these are less likely to happen.