First, you should know that there is no state or federal threshold for how much indoor mold is too much. As of this writing, we are unaware of any local governments in Indiana that have set thresholds. Most government agencies follow the EPA on mold. On mold thresholds, The EPA says, "Standards or Threshold Limit Values (TLVs) for airborne concentrations of mold, or mold spores, have not been set. Currently, there are no EPA regulations or standards for airborne mold contaminants."
Why are there no standards for acceptable mold levels? Because mold is common in nature, often at very high levels, and mold exists everywhere we live, work, eat, and play.
When is Mold Testing Necessary?
If there are no federal, state, or local standards for how much mold can be in the indoor air, what is the point of testing? There are times when having test results can be informative and helpful. This usually depends on what you already know about the situation, and what you hope to learn.
Often, mold testing is not needed. For instance, there is no reason to determine the type of mold before remediation; all types of mold must be removed in the same manner. It is also unneeded, in most situations, to do mold testing when there is no reason to suspect a mold problem. The Centers for Disease Control and Prevention states in their FAQ:
"Generally, it is not necessary to identify the species of mold growing in a residence, and CDC does not recommend routine sampling for molds. Current evidence indicates that allergies are the type of diseases most often associated with molds. Since the susceptibility of individuals can vary greatly either because of the amount or type of mold, sampling and culturing are not reliable in determining your health risk. If you are susceptible to mold and mold is seen or smelled, there is a potential health risk; therefore, no matter what type of mold is present, you should arrange for its removal. Furthermore, reliable sampling for mold can be expensive, and standards for judging what is and what is not an acceptable or tolerable quantity of mold have not been established."
In other cases, though, mold testing might be a good idea. Listed below are some reasons you may want to consider mold testing.
- You need to prove a substance is mold for legal reasons
- You suspect mold in an area, but none was found in the visual inspection
- You want to know how much and/or what types of molds are present in indoor air
- You want to compare the amount of mold in your home to "average" or "normal" homes
There are other reasons to perform mold testing, but those are the most common. In any case, if testing is to be done, you should ensure you are using the right test to get the information you want.
Types of Mold Tests
There are many different types of mold tests, with some new and interesting ones developed in recent years. Below we list some of the most common tests, how they are performed, and the information you can hope to get from them.
Air Sampling/Mold Spore Trap
Mold Spore Trap, or MST, is one of the most common types of mold test performed and the only type of test some companies do. This is a method of collecting air to determine what particles are present and the quantities that exist at that time. The air samples are taken with a vacuum pump that impacts a specific amount of air onto a sterile cartridge. Mold, dust, and other substances are trapped in the cartridge and analyzed in the lab to determine the contents.
Generally, one sample is taken in each area of concern or each level of the home and an additional sample is taken outdoors as a baseline. The lab compares the samples to determine if the types and amounts of mold indoors are similar.
ERMI is a newer test that takes a dust sample from surfaces in your home and compares them to a table of data collected in over 1000 homes across the country. Through this comparison, it is possible to get a general idea of the overall mold burden that any particular home has.
The test works by using a DNA sampling method patented by the EPA that assigns a “spore equivalents” based on the amount of DNA that is detected. The advantage to this type of testing is that specific mold types that are present are absolutely identified, unlike other methods which require a visual identification by microbiologists.
Several doctors, concerned about potential health effects that their patients are experiencing, are choosing this testing method as a way to determine exactly what types of mold are present and that their patients may have been exposed to.
A test kit can be ordered online and done by the average homeowner, or we can perform the test for you and help you to understand the results.
Sterile swabs or strips of tape are used to collect samples from a surface. The tape or swab is placed on the area to be tested, picking up the particles. These samples are then examined in the lab.
In some cases, bulk collection of affected materials can be collected, sealed in a bag, and sent to the lab for direct examination.