Mold Testing

What is mold testing?
As a general term, mold testing consists of collecting a sample from the air or any suspected surface. A professional mold inspector will test the air or a surface through sampling to figure out exactly what kind of mold is present and whether that particular mold species has the competence to thrive in the tested area or environment.

How is mold testing performed?

• Air sampling – how to test for mold spores in the air
There are several ways to collect air samples and perform analysis on them. The frequently used method involves a collecting device that traps the spores by allowing a known volume of air to pass through it. When mold spores in the air pass through the collecting device, they get stuck onto a sticky medium called a culture dish. The culture dish has a sticky medium containing the trapped spores that are then sent to the laboratory for the analysis.
This method of air sampling is least detrimental to the spores and allows more precision in the identification of the mold species. In the laboratory, the dish is taken out and a few drops of stains are added to the medium containing the trapped spores. The spores then absorb the stain and become visible when observed under a microscope. Another less common analysis method is to allow the spores to colonize or culture, and then observe different colonies of mold that will grow on the culture medium.
One of the frequently asked questions is – are air tests for mold accurate? A single mold test from the air is not very accurate. This is the reason why professionals in this field do multiple air sampling. The mold tests through air sampling give an estimation of the spore’s concentration in the environment. As the concentration of mold spores fluctuates from time to time and area to area, the professional will perform mold testing throughout a set period at different intervals from particular places in your house. This helps yield results with higher precision.

• Surface Sampling – how to test for mold spores on surfaces
Surface sampling is the collecting of spores from the multiple common surfaces such as countertops, walls, and other typically contaminated surfaces. The spores are collected mostly by two techniques:
1. Swabbing: The swab test employs a swab made of cotton to scrub the surface to be tested. After wiping different surfaces, the swab is later sent to a lab.
2. Tape lifting: A proportion of tape is cut and is placed on any areas to be tested. The tape is later pulled and placed on a microscope glass slide. This slide is then sealed and sent to the microbiology laboratory.
These techniques are pretty self-explanatory. The samples are then sent to the lab for examination under a microscope to detect the presence of mold spores. Surface mold testing does not give an accurate representation of the concentration of mold spores. Surface sampling is performed along with the air test for mold. During the rainy season, or under damp, moist conditions, the scattering of suspended spores in the air is diminished. The mold spores tend to settle on the surfaces of various household objects. As a result, air sampling may not yield complete coverage.

• Bulk Testing
Another method for mold testing is the bulk testing method. In this method, a small section of the various sample materials is taken and forwarded to the laboratory. The microscopic examination of spores on the material chosen is observed. A spore-absorbing dye or stain is added to make the spores visible under the microscopic lens.

Under what conditions should mold testing should be performed?
The leading factors involved with having a mold test done in your home are:
• You perceive evidence of molds such as a moldy smell or mold manifestations.
• To specify the type of mold in your home.
• To discover all the possible areas of mold growth.
• For testing the quality of indoor air based on the concentration of mold spores in it.
• As a post-test – to make sure that mold has eliminated or not after the mold removal procedure.


When is mold testing not required?
The trick is to recall a straightforward rule: as soon as you see the mold, it must be removed. Otherwise, testing is usually unnecessary at this point. The test is irrelevant at this point because you can see the mold and test will only reveal the species of mold growing, so finding out the mold type is useless. If it is growing, then all you need is a professional to make an inspection on all possible areas where mold may be growing and remove it, following proper mold remediation and mold removal principles.

Do Home or DIY mold test kits work?
Buying DIY mold testing kits is nothing but money down the drain; here’s why:
• The test results obtained from the DIY mold testing kit are mostly fallacious or confusing.
This is usually because of the mistakes in the sampling process. If the first step is incorrect, then the results can be misleading. The best practice is to allow professionals to do their job.
• If there is no visible mold, but you are experiencing some allergies or moldy smells, what’s important is to have an inspection done by the professional to discover where the mold is hiding. The test will give a positive result if you are smelling the mold. Since you might not know where the mold’s hideout is and related issues, or if you are allergic to molds, coming in contact with unforeseen mold colonies may worsen that. So, the mold test kits contribute little to help you pinpoint the problem or indicate the seriousness of the issue. Inspection before testing is a must, and it requires a specialist!
• To be honest, the mold is found in all corners. Yes! Every house has some number of spores floating in the environment. Even though such a small amount is not harmful, but your mold test kits will surely detect those, making you go in a panic. These kits are nothing but a waste of time and money as they do not yield any meaningful results for you.

Still, need more reassurance? Don’t believe us! Below is what the U.S. Government EPA says, verbatim:
“Sampling for mold should be conducted by professionals who have specialized experience in designing mold-sampling protocols, sampling methods, and interpreting results. Sample analysis should follow analytical methods recommended by the American Industrial Hygiene Association (AIHA), the American Conference of Governmental Industrial Hygienists (ACGIH), or other professional organizations.”
Here’s another explanation with a simple example! The Mold Testing kits we are familiar with are the “sedimentation” plates like the Petri dishes that have to be kept open for a short time to allow spores to settle. This is comparable to placing a plate of fruits outside for some time and then exploring whether mold will grow. Certainly, it will grow. It will sprout out of nowhere, even in your fridge. If any food is kept in the fridge for an extended period, the mold will grow. However, this will not indicate that your house has a mold problem.

Mold Inspection Before Mold Testing
As mentioned earlier, mold inspection is crucial before performing any mold test. Why? Because it will save you the cost for mold testing. How? If the professionals during mold inspection uncover the sanctuary of mold, then you won’t have to do any mold testing. You would proceed straight to the mold removing stage.
On the contrary, if the inspection does not reveal any mold hideouts, but you still doubt that your house has a mold issue, don’t give a second thought to contact the professionals for the Mold Test.

What is considered a high mold count?
Not all species of mold growing in your homes have a similar tendency to pose a problem at a particular concentration.
For example, mold species like the Stachybotrys and Memnoniella are toxic and are considered to be an issue at 50-200 spore count, which is still very low.
In comparison, Penicillium/Aspergillus and Cladosporium only become a problem when spore count is as high as 1500-3000, as they may start to become apparent.

How much does it cost for mold inspection/testing?
For a professional mold inspection, householders, on average, are paying $649. Although the overall cost of inspection and testing depends on the dimensions of the house, either big or small, as well as the location, it may cost between $293 to $1,013 for homeowners. Compared to this, you can buy a home mold testing kit only for $40 max. Yet again, as we have mentioned, a home mold testing kit cannot substitute a comprehensive evaluation.

DIY Mold Test Kit VS Professional Mold Testing
DIY mold testing kits can range somewhere between $10 and $40. They are readily available at almost all large-scale distributors, retailers, and home improvement outlets. However, the results will still not be promising and depend on how and where you do it.
From our experience, only a competent evaluation by a certified pro can help you truly understand the magnitude of the problem.

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