More on the Interpretation of Mold Air Samples

Sep 15, 2017

Are you staring at the results of mold air samples and struggling to figure out what it all means?  Let me try to help you.

The most common method used for mold air testing is uses a spore trap cassette. Because there is always a background amount of airborne mold spores, a key step in collecting air samples is to have a “reference” sample collected from the outdoor air at the time of the indoor testing. Since there are no guidelines on acceptable mold levels in the air, an outdoor sample is the best tool for interpreting the results of the indoor samples. Without the outdoor sample, you are limited in what you can gather from the results of the indoor samples.

There are various D.I.Y. air tests you can pick up at your local hardware store requiring you to place out a petri dish for several hours. Most of those tests are not very helpful in giving you any sort of usable data to evaluate the air in your home and as a general suggestion should be avoided.

Update: April 2021:

We thank you for all the interest in this blog post, and appreciate how many of you reached out with your questions. At this time, we are no longer taking submissions for comments, but feel free to check out some of the past interpretations we have provided for others below.