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Interpretation of Mold Tests

mold tests, clipboard, interpretation

In Chicago and beyond, there are some mold inspectors that don’t really do an inspection at all.  They do basic mold testing, such as collecting a few air samples, and neglect to do a visual inspection of the home or evaluate the moisture problems leading to the growth. To make matters worse, these inspectors typically hand you a laboratory report and make you fend for yourself for one of the hardest parts: the interpretation of the mold tests.

In this blog post, I intend to freely assist anyone that had a sub-par mold inspection and is left with more questions than answers.  Post your questions at the bottom of the page in the “Leave a Reply” section.  Please note that it asks for your email address, but it will not be displayed on the blog.

Although this designed for people in the Chicago area, I would happy to answer everyones questions.  The more details you provide, the better!

Finally, if you would like to speak with us directly, you can purchase a 30 minute phone consultation for $98.  Or if you are looking for a mold test in Chicago, give us a call at the phone number at the bottom of the page.

UPDATE 9/18/17:  Although I’m not accepting or responding to new questions here, Dylan McIntosh at our office started a new blog post where he is actively responding to questions: More on the Interpretation of Mold Samples.

Ian Cull

Ian Cull is a nationally recognized expert in the field of indoor air quality. He is the Chief Science Officer of Indoor Science, a company he started in 2004. He speaks around the world on air quality topics and is a training provider of the Indoor Air Quality Association. Mr. Cull is a Licensed Professional Engineer (PE) and Certified Industrial Hygienist (CIH). His degree is in Environmental Engineering from the University of Illinois - Urbana Champaign. Mr. Cull has developed 50 air quality related courses for the IAQA University and is the author of the book, “Fundamentals of Mold Remediation”. In his words… “Besides being passionate about indoor air quality, I enjoy cycling, music, the Chicago Bulls, and having fun with my three kids.”

167 thoughts on “Interpretation of Mold Tests

    Really concerned parents to be, my wife is 6 months pregnant. Story goes as following, moved into a new construction apartment just under 2 years ago. 5-6 weeks ago an odd smell began in the master bath (master bed attached). Plumbers came/went and then we spoke with others (my contractor) who believed the smell to him was moisture. So had a report prepared by specialist. The specialist detected moisture in shower walls and the air test revealed as follows:

    Outside – total raw count of 83; count/m3 of 3,590
    Master Bath – total raw count of 14; count/m3 of 660
    Master Bed – total raw count of 18; count/m3 of 770

    Outside – A/P raw count of 5; count/m3 of 200
    Master Bath – A/P raw count of 0; count/m3 of 0
    Master Bed – A/P raw count of 4; count/m3 of 200

    Outside – Badiospores raw count of 64; count/m3 of 2800
    Master Bath – Badiospores raw count of 8; count/m3 of 400
    Master Bed – Badiospores raw count of 5; count/m3 of 200

    Outside – Chaetomium raw count of 0; count/m3 of 0
    Master Bath – Chaetomium raw count of 0; count/m3 of 0
    Master Bed – Chaetomium raw count of 1; count/m3 of 40

    Outside – Stachybotrys raw count of 0; count/m3 of 0
    Master Bath – Stachybotrys raw count of 2; count/m3 of 90
    Master Bed – Stachybotrys raw count of 5; count/m3 of 200

    There is no visible water damage in either the bathroom or the bedroom and obviously no history of water damage given that it is brand new. We have had an IQ air filter running in the master bedroom frequently as well. What is particularly concerning to me is the presence of Chaetomium and Stachybotrys in the master bedroom where we have never smelled anything other than when the bathroom door was open; I understand from some reading that those can be considered elevated levels. We have had an issue with the HVAC in the master bedroom (basically have been unable to service the unit, ie. change filter or access the drip pan). We have not used the bathroom in two weeks and have had the door closed. Not sure what to do here. Specialist has recommended remediation of the bathroom which I am happy to do but how do solve the bedroom problem? Your help would be greatly appreciated.

    A few months ago my son who was just released from the hospital for an open heart surgery got an upper respiratory infection shortly after moving into our house. Later we found that the house had been previously flooded and was inadequately cleaned. The lab results came back with Aspergillus/Penicillium 94,968 spores/square in and Chaetomium 269,032 spores/square in. Additionally it was found that Hyphae and Fruiting Structures were observed. Could this have adversely caused my immunocomprimised son health issues?

    Thank you for doing these! I read through every post but didn’t see anything similar to mine. My husband and I are renting a home that we have lived in for 6 months now. I’ve always had allergies in the morning since we moved in and suspected air quality issues. It wasn’t until our 2 youngest children (3 and 5) were regularly becoming ill and everyone had a cough only while in the home that we decided to have testing done.

    We live in Houston Tx with high humidity and a lot of downpours in the last few months. We noticed a leak around an exhaust vent two months ago and brought it to the landlords attention. He dismissed it and said it was an old stain we just didn’t notice before. Last week, we had a very large storm and I videoed it dripping. I could also hear a drip behind the drywall in the closet.

    After testing, here’s the results:

    Inside Master Bathroom:
    Ascospores raw 1. Count/m3 13. % of total 7.5%
    Bipolaris|Drechslera raw 2 count/m3 27. % of total 15.5%
    Cladosporium raw 2. Count/m3 27. % of total 15.5%
    Curvularia raw 5. Count/m3. 67. % of total 38.5%
    Myxomycetes raw 2. Count/m3 27. % of total 15.5%
    Pithomyces raw 1. Count/m3. 13. % of total 7.5%

    Outside near garage:
    Ascospores. Raw. 23. Count/m3. 307. % of total 41.0%
    Aspergillus|Penicillium. Raw. 2. Count/m3 27. % of total 3.6%
    Basidioapores. Raw. 14. Count/m3 187. % of total. 25%
    Cladosporium raw 15. Count/m3 200 % of total. 26.7%
    Myxomycetes. Raw. 2. Count/m3. 27. % of total 3.6%

    Do we have anything to be concerned about? If not, we’ll stick through the rest of the lease and not worry about the dripping ceiling.

    Thanks for your help!