The presence of mold in your home or business can be potentially dangerous to yourself and anyone else that may be exposed, especially for asthma sufferers. By seeking out air quality mold test results, you can make your home or business safer for everyone.
Allergic reactions to mold are not uncommon, and they can occur immediately or with a delay. The allergic responses are similar to hay fever symptoms such as runny nose, skin rash, red eyes, and sneezing.
To achieve peace of mind, you may want to get air quality test results for your home. The EPA suggests only testing under very specific conditions, so in general, a qualified inspector is much more useful to find out if a mold or moisture problem exists. However, there are some occasions which will warrant additional air quality testing. It is best to test in different locations at several different times in your home, so you can get a more accurate idea of what kind of mold problem you may have.
What Type of Mold Testing is There?
There are three common methods of mold testing. Air sampling is the most common way to test for the level of mold. A sample of the air inside and outside is taken, and the levels of mold spores are compared from each other. Air sampling will commonly provide a positive ID on the existence of non-visible mold.
A surface sample measures the number of mold spores dispersed on indoor surfaces with tape and dust samples.
A bulk sample is the removal of materials from the contaminated area. This will identify the concentration of mold in the sample.
Air Quality Testing
Air sampling is the most common method of mold testing. There are four ways to quality test air for mold.
A sporetrap non-viable sample is slightly controversial, but it is still the most common method of testing mold that is performed in the industry. A calibrated pump will draw a certain amount of air over a greased slide. This method of collecting spores is known as impaction. A direct microscopic exam is then performed on a portion of the slide. The lab will deduce the number of spores that are present per cubic meter and can identify many of the common types of mold. One of the problems with a direct examination is that some common types of mold cannot be differentiated. Also, some of the heavier spores may not be aerosolized, which can lead to underreporting on these air quality mold test results.
The second most common type of sample is a petri dish, also an impaction type collector. The petri dish is placed under cap with a small hole while air is drawn over it. The petri dish is incubated afterward, and the number of different mold types are counted and identified.
One of the strengths of this method is the different types of mold can be differentiated. This is an invaluable feature, as there can be hundreds of species within each type and some can be more toxic than others.
Some of the sampling method’s weaknesses include the fact that differing types of molds prefer different kinds of temperature, moisture levels, and growth media, but the lab will simply use the standard setting unless otherwise instructed. To get a more complete analysis of all the viable airborne spores in one area, numerous petri dishes using different growth media must be used and then incubated under different temperature and moisture settings. Some molds do not grow well under lab conditions, and other molds can produce chemical weapons to kill neighboring colonies, reducing the count of the sample for both species.
MVOC (Microbial Volatile Organic Compound)
Molds will grow under wet conditions where they have food. When the mold is eating, it will produce MVOCs. An air sample can be collected in a canister or tube, and the lab will analyze the air sample for a certain number of MVOCs.
Most MVOC tests are limited in the fact that they do not analyze for every MVOC. Most MVOCs are not directly related to a single mold species, so deduction from only MVOC data can be limiting. The musty smell associated with mold is the MVOCs in the air.
Mycotoxins are the secondary metabolites that are created by fungi. They are essentially self-produced chemical weapons that will harm other fungi, and can also be responsible for death and disease in humans. Primarily the danger lies in ingestion, but inhalation can also be damaging as well.
The lab will utilize polymerase chain reaction (PCR) analysis to count and identify the mycotoxins in the air samples, which are collected in filtered cassettes. This process is automated and has a much higher confidence rate. There are few environmental consultants that test for mycotoxins.
Surface testing will test household surfaces by taking samples to find out the amount of spores throughout the home. Samples will be taken via tape lifting, swabbing, or other methods, and the lab will then examine the samples to find any abnormalities.
The results can vary, as spores caused my mold growth are not evenly dispersed throughout the home and will change over time. Surface testing cannot correctly identify the concentration of mold in the air.
Bulk testing will involve the collection of material from the building being tested. The laboratory will then examine the materials under a microscope to find out if you have a mold problem. Bulk tests are a good way to learn the details about the concentration of mold in certain areas of the home.
Interpreting Air Quality Mold Test Results
So your inspection is done, and the results are in, but how do you read the results? Typically, you will have a certified professional to help you out with the results, but this is not always the case.
Sporetrap lab results will usually include at least one outdoor air sample with a few indoor air samples. The sample of outdoor air will serve as the control, to compare to the indoor samples. There can be a large variation in sporetrap samples, and since the significance from so few samples may be limited, most labs will simply show a chart with the types of mold found and how much.
Cultured results can use different set points determining low, medium, and high probability of mold growth, depending on the lab. Typically they will follow the Healthy Home Standard’s suggested guidelines for interpretation.
The last two air sample types have much less standardization between laboratory results. Usually the results will contain written guidelines to determine how much of each type has been found and what levels may be present, but if there is still confusion, consult a professional.
Occasionally mycotoxin results may be paired with blood test results. If pathogens are found in the blood, the person’s home and work will usually be tested to find out the source.