How do experts test for mold?

We are frequently get asked how an expert tests for mold. Most people don’t know that a trained professional will never test the air in your home or office to look for mold spores. There are several reasons why pushing the air won’t work, most notably:

Mold is everywhere. There’s likely more mold in your eyelashes than all over the place combined ;

Tiny amounts of mold release vast quantities of spores into the air; and Most importantly

Airborne particles from any source may end up on a surface where they can be detected, often with sophisticated equipment specialized for chemical detection or DNA analysis. You may have heard of devices used by law enforcement officials who want to test surfaces for fingerprints – these pieces of equipment exist for mold testing, too. Chances are you wouldn’t be able to afford it if you wanted to buy one yourself!
These reasons make testing air for mold a complete waste of time and money. If an expert says they’re going to test your property’s atmosphere for mold, it’s because they do not know what they are doing or trying to sell you something completely unnecessary. It may even be unethical, but I guess I shouldn’t go there…

So what does an expert do?

The first thing is to look at the house (or office) with their naked eye; The next step is usually taking samples; Lastly, the trained professional will analyze the models in their lab. Taking samples requires using a very accurate instrument known as an optical particle counter. This type of equipment is not the same as a regular air sampling pump that you may have seen in a hardware store.

Optical particle counters can be calibrated to differentiate between particles in the 0.3-3 micron range, where mold spores fall in size. Airborne particles in this size range are generally too big for human respiration and won’t enter your lungs to cause any respiratory problems but will settle on surfaces after being released into the environment from building materials, household objects, or dead organic matter such as leaves or other plant material.

There’s also another technique called tape sampling that has been used for many years by testers and building scientists. Still, it’s giving way to optical particle counting and other methods that are less subjective and more accurate. Tape sampling often leads to false positives because it utilizes a technique not entirely understood by the scientific community.

The best tape sampling result is still only an indication of the material sampled, not necessarily of airborne particles in your indoor air.
A qualified expert will also interpret the test results correctly, even though there may appear to be some discrepancy between tests that utilize different techniques or equipment. Remember that just like any tool, each testing method has its strengths and weaknesses, which must be considered before concluding what’s going on at your property.