Mold test results

I did my first mold test the other day and just got the results. I use pro-lab and used the swab and air-o-cells.
I called the lab and they said things were not good but what is good and bad results.
I had Stachybotrys at Raw count of 4 and Spores/M3 at 27.
I had Penicillium/Aspergillus at Raw 688 and Spores/M3 at 4587.
I had Cladosporium at Raw 12 and Spores 80.
I was not able to do an outside test or garage being there was no garage and it was like 20 degrees outside.

Without the outside control sample, your results cannot be validated.

There is no indication of stachy count on your report.

That was only one sample i attached. That was the worst Pen/Asp report of them all. The basement had no Stach, and the main floor and upstairs did.
I understand without outside control, it is tough. But the visual problem was down stairs, so i did one on each floor and that sucks.
Just was curious on what other counts people have had and how they compare?

I recently took a Mold certification class sponsored by NACHI & Pro-Lab. The class was taught by the Environmental Solutions Association. The class was excellent and well worth it.

According to ESA, if you have visible mold, the proper sampling protocol would be to take a swab sample, plus take interior and exterior air samples.

I recommend that you contact ESA at for more info.

ESA is good.

As Jay indicated, without a outside sample to compare ,your results are almost useless. Mold spores are part of life, & will travel in & out of our homes. What we want to do is not create a breeding ground for them inside. ie: wet,dirty,humid area’s, etc. If your outside sample has readings equal to or greater then your inside readings, you may not have that big of a problem. Don’t go to court with your findings. An Industrial Hygienist will hang you. Be carefull! Just my 2 cents Doug

I understand the outside air test is important. My question is for my own curiousity. This was my first one and i am imagining that i will not do a ton of these and was curious what kind of results/numbers others are getting both inside and out? I took the Pro-Lab/NACHI/ESA class also. AGAIN, i understand the outside sample is important but at that time and with everyone wanting things now, i could not do an outside. I talked to a Pro-Lab person and they said the Levels were high no matter with an outside test or not. My pen/asp levels were high and if there is a Stach count at all, that is not good.
Anyone care to share their results of test they have done? You won’t be telling they are high or low just curious on levels you have gotten. If you want to go into more details, that is great also.

The outside sample is MANDATORY if you are working to find out if a client has a problem. The only way to determine if your client has a problem is to retest. IMHO you have provided a service to your client that is of no use. Did you charge the client for the samples that you took? If so I would contact the client and tell them that the tests were inconclusive and that you needed to retest at no charge.

You must do some type of outside test. You should have xplained to the client that you could not test because of the outside temp.

Our instructor encouraged us to get an outside reading, if you can’t reschedule, Then if that was not possible get one from the garage if the temp is high enough.
His last option, which he discouraged, was to get a comparable from a room farthest away from the suspected mold.
I think this is a learning process for all of us, I would go back and do two more air samples, one in and one out, at no charge.

I’m looking at getting into mold this spring.

Good luck


Yes, I could not reschedule so i did the furthest room and upstairs as the suspect problem was in the basement of a 2 story home. Now everyone is slamming me for it. I understand the outside one is important but i couldn’t do it. So now i am just asking people for what kind of results they have gotten just for my own comparison and education.
The basement did not have Stach and the main and upper floor did. I thought that was weird. And therefore i have questions for some pros who have done many of these.


Did you tell the client that the samples you were taking would only identify the type of spores found. That without the outdoor sample you would not be able to tell them if they had an elevated condition or not? That the report would state inconclusive?

High in relation to What?

Without a baseline reference the results are not relevant to anything.

Test would have to be reported as inconclusive and incomplete.

I guess basically Pro-Lab said it has Stachy and if you have that, that it is not good.
Thanks and if you all are saying no good on the test due to no baseline, then i will take it from there.

Good Luck Andy

I hope that everything works out for you.

If what you want is Quantitative, you’re correct. But I believe if what your after is a qualitative answer (what kind of microbial growth do we have?) then a control may not be required.

It sounds like Andy may have been attempting a Qual analysis with a general IAQ type (which is both qualitative and quantitative) and thus mandated a control to provide meaningful results.

CC (our resident, non resident IAH) might be of more help here…

Exactly Mike!
I forgot about that person. Thanks for that Mike.
Man these guys are tough.
Have a great weekend.

There’s no question that the numbers in your report are evidence of colonizing mold. A control sample is necessary, however you can tell by the numbers in the interior that there is a mold issue.


Don’t want to rain on your parade any more but look at this as “on the job training” for why not to do mold testing, if your not qualified to do it. Notice I did not say certified. Many certifications are not worth the paper they are printed on. Any lab that offers .5 - 2 day certifications on a complex subject like mold are just setting you up for a lawsuit. BTW - do you have E&O for mold testing?

When I was investigating this as a way to expand my business I stumbled into the same issue you are facing - how do you interpet the results? Customers look to us for this information and reasonably expect us to interpet the results. Unless you have the training its very difficult and then especially with mold, your chances of the results (and interpetation) being wrong, are pretty good. Any lawyer who gets you up on the witness stand, will rip you apart.

Today when I am ask about mold I tell the client I only do moisture intrusion investigation because to have mold, you gotta have a source of water. As far as mold goes if you can see it or smell it in a house, its bad. It doesn’t matter what type it is, its gotta go!

Exactly my protocol, as well.

When I was young and growing up in South Texas, spring cleaning meant gallons of Clorox, packages of stainless steel wool, and lots of elbow grease cleaning the mold out of the bathtubs and showers. Needless to say, but I’ll say it anyway, I don’t do spring cleaning anymore, preferring to clean on a daily basis so that I don’t have to set aside a whole weekend or more doing spring cleaning. I also don’t do mold testing, of course, especially since I live in a desert. I’ve been asked about it twice in 4½ years and both scheduled inspections with us.