Where to Start with Mold Investigations and Sampling

We receive calls daily about mold concerns and indoor air quality testing. Many potential clients do not know where to start and have become overwhelmed, led by searching the Internet and getting conflicting information. I will try to explain that indoor air quality tests are like going to the doctor to get a blood test. What are they testing for? The same applies to indoor air quality, including fungi, mycotoxins, VOCs, asbestos, and much more.

When a potential client contacts us, we want to know what prompted the call. Weather is related to health concerns, a doctor's prompting, a prior water event, visible mold, or an “odor.” Often, an odor can be perceived by individuals hypersensitive to a specific mold that others may not sense or “smell.” Some mold could be not apparent in a wall cavity and emit an MVOC that many clients may detect, feel, or smell. Once we pin down their concern about mold, we need a history of the home. We conduct an interview of the client’s history, other locations they may frequent, other potential locations they may have been affected, and any prior water incidents in the house.

Many of our clients show specific health or physical reactions to certain molds, which others in the house or building do not affect. However, with prolonged exposure, some individuals’ immune systems may wear down, resulting in specific physiological reactions and responses. The client may opt to change living locations for a short period to see if there is a change in their symptoms.

Mold Sampling Options

SPORE TRAPS: When we perform spore trap sampling, we compare the indoor and outdoor mold levels. Since mold is virtually everywhere, we are looking for indoor amplified mold. The rule of thumb is that anything indoors with a 10x higher spore count concerns the ACGIH. However, lower levels of Stachybotrys and Chaetomium may indicate a hidden concern as these molds do not typically show in higher levels of conventional spore trap testing unless there is a significant issue. This mold also produces mycotoxins that can present significant health risks. These can include central nervous system manifestations, including headache, irritability, lightheadedness, sleeping difficulty, concentration problems, and mental fatigue. Alopecia, rashes, eye irritation, and various constitutional symptoms are also frequently reported. The upside of spore traps is they are great at identifying specific mold families. However, the downside of spore traps is that they have a reproducibility accuracy greater than 25%. This means that if we take multiple samples, day after day, and send them to various labs, we may have a deviation more significant than 25%.

MYCOMETER: Enzyme-targeted fluorogenic Detection (ETFD) is a lesser-known but highly accurate method for mold sampling. This testing method offers a rapid and accurate quantification of fungi with a less than 6% variation of repeated tests. When using the FAI or fungi to allergen index, we can obtain an accurate image, including mold growth on allergens. With a swab, we can collect a surface sample and get accurate information on mold activity on various surfaces and within the dust on the surface. Another valuable part of this test is that we disturb the air with a small blower referred to as activated air sampling.

This system has third-party verification, has been peer-reviewed, and is an accepted method in ASTM Standard 7338.

MYCOTOXINS SWABS: We can sample mycotoxins for the presence of mycotoxins with swabs or wipes and even MVOCs with air sampling. This may help identify potentially concealed viable mold growth.

ERMI: One common issue is the lack of awareness about the various available tests. As a result, many individuals end up with insufficient results from consumer-based testing. These tests, such as the so-called “Swiffer: ERMI tests, may not provide a comprehensive picture of indoor air quality, potentially missing crucial issues. The issue with this test is dust is everywhere, and the results can give inconclusive data to the sampler and potential abatement company. Some labs will not analyze these tests due to the risk of background debris from the collection methods. A carpet ERMI test is much better, but according to the EPA, it should be used as a research tool. The carpet ERMI test is excellent at showing the history of the building.

VIABLE TESTING: Viable testing can be helpful when you or your doctor want to know specific molds. These are not a common sample, but they are useful. This is where we take an air sample, impact over an agar, and culture at a lab for mold speciation.

With any air sampling, potential clients want to know where they should have a sample taken. Again, this is an important and somewhat tricky question to answer. Without knowing the house's history many times before the current occupant, there may be no knowledge of a prior water event.

I always like to put air testing into perspective. It is like going into the ocean without a fish finder and dropping nets. We may drop them right at the school, but part of the school of fish is somewhere else and is not being detected but is present.

This is also why checking your insurance provider's CLUE report (comprehensive underwriting evaluation) for any prior water damage-related claims is essential. Also, if the client is considering purchasing a flip, they should be aware of the potential that water damage or mold may have been intentionally covered over and not correctly abatement. When there is a known history of abatement, always check to see if a third party took post-verification samples.

With any testing, there are limitations as to conditions and specific changes that may occur. These can include the weather, open windows, bringing contaminated furnishing from another location such as storage, removal of carpet can be a considerable factor, remodeling, improperly controlled humidity, water intrusion, internal leaks, and the home being too tight (may need a heat recovery ventilator (HRV)).

We have developed a mold investigation procedure to help our clients understand their options.

Mold Investigation and Sampling Levels

Level 1: Mold Inspection (Air and Surface Sampling)

Option 1. We will perform an FAI (Fungal to Allergen Index) air sampling utilizing the Mycometer system based on an Enzyme-Targeted Fluorogenic Detection (ETFD) technology. This will help locate and identify areas at risk for mold and activity with rapid results and be highly accurate for quantifying fungi and allergens.

Option 2. We also offer conventional spore traps to identify the type of mold present in the air. We take one sample outside and one sample indoors to compare against the outside reference.

Option 3. We can take random surface samples with the Mycometer swab to help identify mold growth and determine whether mold is present in the dust sample.

Level 2: Mold Inspection (Combined Sampling)

With a level 2 mold investigation, we combined the Mycometer FAI air sampling with a conventional spore trap to obtain optimum sampling results by comparing both sample data.

Level 3: Mold Inspection (Visual)

Our inspector will perform a limited visual inspection evaluation of the building to identify areas of visible suspected mold (fungi) and to try to identify the cause. This will help offer recommendations for the homeowner or mold abatement company on a course of action for mold abatement. Our inspector will use thermal imaging and infrared scanners to locate high humidity and areas at risk for condensation, as well as moisture meters, and identify areas of suspected moisture intrusion, leakage, or other sources that could promote mold growth. The inspector will then issue a narrative computer-generated report with photos so the client can clearly understand the scope of the concern for moisture and mold risks. The client should prepare the house with access to all walls, mechanical systems, and the attic, and all windows and doors closed for 24 hours before the inspection.

Level 4 Mold Inspection (Invasive Inspection)

A level 4 inspection or investigation determines the source of the moisture. It may include an invasive investigation, opening the wall surface, and closing off another surface to locate the extent of activity or damage that may not be visible during other mold testing protocols and procedures.

For mold testing and investigation, contact Showalter Property Consultants.

www.inspectmaryland.com