At this point I am assuming that you either know you have mold (i.e. you can see it) or you highly suspect you have mold (i.e. you have mold illness symptoms) and you are ready to find out what is going on in your house. The standard operating procedure at this point is to hire a Certified Industrial Hygienist (CIH) to come to your home and take several different types of mold samples. I can’t emphasis how important it is to find a CIH that you trust and this is not a time to hire a fly by night company. Although the sampling methods are really not that complex when you are talking about your family’s health this is no time for a half ass effort. If this is an insurance claim DO NOT LET THE INSURANCE COMPANY HIRE THIS COMPANY DIRECTLY. I will go into the reasons in the insurance section but basically there is a high potential that you will get screwed if you go this route. Anyway the point of any mold testing is to determine what type of mold you have, where is the main source or sources and how to get rid of it. Let’s begin:

Testing Methods

Basically the CIH is going to first try to find the source of the mold, its reservoir. Below is some of the more common tests performed:

1. Swap Sample - A swap sample is basically taking a giant Q-Tip rubbing some mold on it and depositing the mold on to a petri dish. At this point the mold is grown which takes a couple of weeks and then the laboratory personnel determine what type of mold you have as well as what species of mold it is. For example they grow a mold and they discover it is Aspergillus. Great, Aspergillus has over 30 different species, some harmless and others very toxic. Without knowing they species it is really difficult to tell how harmful your mold could be. If any CIH tells you that this is not important, don’t hire him or her. Species is important.

2. Air Samples - Generally the CIH will use an Air O Cell testing method, which is sort of, like hooking a vacuum cleaner to a filter. This vacuum sucks through the filter between 30 to 150 liters of air catching air particles in the its filter. The filter is then sent to a lab to determine what type of mold spores it caught. They will take samples throughout your home (i.e. in several rooms) and they will also take a couple of samples outside of your home. The outside samples are taken to determine the basic line of mold spores in your home. For example, if outside the Aspergillus count is 350 particles per cubic meter (ppcm) than if your home only has a problem if it is higher than that. What is high? They say anything over 1000 ppcm. In my home they found they found 16,000 ppcm but I have seen numbers much higher. The downside of this test is it does not allow for determining the species of your mold. This isn’t a tremendous problem if you know the source of the mold because you can species it there but if you don’t then I highly recommend the Anderson test. This test basically does the same thing however instead of using a Air O Cell filter they slam the spores caught in the air into a petri dish and let it grow like a swab sample so they can later determine the species.

3. Tape Samples - Tape samples are just what it sounds like. The CIH will go around to different items in your home using the tape to lift dust and spores off of items in your home and then put in under a microscope to determine what type of mold you have. This is very important. It is not uncommon to find very few spores in the Air Samples but find high mold counts on your, carpet, furniture etc. This is basically because the spores have already settled (kind of like dust) on your stuff. This type of sampling is also critical for developing a remediation plan, which I will discuss in another section.

4. Wall Cavity Samples - Often mold starts to live in your walls. Generally when the CIH doesn’t exactly know where the source is or believes there could be multiply sources then this type of sampling is employed. The CIH will use a moisture meter to find out where there are potential leaks behind walls. The meter will basically identify high moister areas and the CIH will drill a hole into the wall. The CIH will then take an air sample (see above) through the drilled hole. This method employs the Air O Cell method discussed above and again is limited regarding determining the species.

5. Bulk Sample - A bulk sample is basically cutting out a contaminated portion of your home, bagging it and sending it to the lab for testing. The nice thing about this method is the lab doesn’t have to wait for the mold to grow to figure out what mold and mold species you have. It is common for the CIH to suspect that there is mold growing in the wall and decide to cut out a portion of the sheet rock to get a good feel for what it is. The bad side is if he or she finds a significant mold source, cutting into it and disturbing it sends thousands or millions of spores everywhere. (Bad answer) Ok so if you are going to go this route make sure he or she is doing it in a way, i.e. putting up plastic around cutting off your air condition in the room etc to avoid cross contamination. DO NOT LET SOME IDIOT CONTRACTOR DO THIS FOR YOU. Only let someone who knows what they are doing perform this test.

No matter what type of testing they do make sure they take precautions not to cross contaminate your home. For example if they find the source they should take precaution not to over disturb the site. The goal is to figure out what is not to spread it through your home. Also once complete they plastic off the source as well as any holes they drill in the wall. Spores are made to travel airborne and the eye can’t see them. Be extra careful, as spreading them throughout your home will exponentially increase the cost of remediation. A good source for additional information on testing can be found at the following website: www.aerotechlabs.com/techtips.cfm.