- Sample Types What are the most common sample types? What are more specialized sample types?
- How Many Samples are Needed What is a "typical" investigation and how many samples should be collected?
- What are Some Pitfalls of Not Collecting Samples Samples can tell us much more than we can see with our eyes alone.
Introduction to Mold Sampling
Standard Mold Sampling
- What is standard sampling A review of air sampling, surface sampling, cavity sampling, and dust sampling
- What a sampling strategy should be There is no one size fits all approach
- The importance of an outside control sample It's the relative moldiness that's most important
qPCR Mold Sampling
- What is qPCR sampling and analysis Testing that looks deeper by targeting the DNA of the mold sample
- Which molds does qPCR identify 36 of the molds most commonly associated with mold sensitivity
- The importance of using additional data qPCR sampling alone cannot give the complete picture of a property's condition
Our Sampling and Testing Question and Answers
We often get questions about how we determine which sample type to recommend, why we recommended a specific number of samples, and other questions about our sampling approach. The type of sample and number of samples recommended truly depend on the property and the conditions found during our assessment. If you have questions about the type of samples used or are wonder how and why specific recommendations are made read on to find your answers.
Standard mold sampling is the traditional method for analyzing samples, where direct examination is utilized via a microscope by a qualified mycologist to visually identify the presence and differentiate between different mold types. One of the most common type of sampling in the industry is air sampling. How and why is air sampling used?
- Air sampling is used to determine what types of mold spores are in the air and how much is present at that time.
- This type of sample is collected using a specialized air pump that draws the air through a spore trap which collects particulates from the air.
- Be aware. Air sampling isn’t a tell-all for a property. Air samples are used in combination with the conditions found during a mold investigation, other sample types, and the laboratory results to help get the big picture.
- Air Sampling – Testing the air for the presence of microscopic mold spores.
- Surface Sampling – Collecting of bulk material, swabbing a suspect area, or lifting visible growth using specialized tape. Generally used to confirm visible mold like growth.
- Wall Cavity Sampling – Is used to draw air from within a wall (or ceiling) cavity to again, test for the presence of microscopic mold spores.
At Mold Inspection Sciences, we use science-based inspection processes and procedures to identify potential areas of concern. Utilizing state-of-the-art moisture detection tools, infrared technology, and appropriate sampling, we can confirm the presence of environmental hazards, including the type and quantity of hazard present.
- Laboratory analysis can tell us if it is mold, and it can also tell us if it’s NOT mold.
- Knowing the type and quantity of a specific hazard can help clients find the most appropriate and cost-effective solution.
- Dust Sampling – Used most commonly to check for various contamination levels during an inspection and in post-clearance inspections.
- qPCR Sampling – Gives overall contamination rating and history of the property. Effective when used in conjunction with our CIRS Protocol inspections.
- Bacteria Sampling – Used if contaminated water loss impacts a property, like sewage or other grey or black water events.
- Allergen Sampling – Testing for common allergens like cat, dog, cockroach, dust mite.
- Water Sampling – Used to determine water quality and assess conditions like bacteria, heavy metals, nitrates, nitrites, turbidity, pH, and others.
After 19-plus years of conducting investigations, we can honestly say, there is no “typical” investigation. It truly depends on the assessment, the property’s unique needs, and how those living, and working are impacted. The property conditions and suspected issues will dictate how many samples are appropriate for each investigation.
This is based on the property itself. Conditions play a substantial role in determining a sampling recommendation. Any area that’s impacted by some degree of moisture will warrant some degree of sample recommendation. At a minimum, an air sample will be recommended and if there is visible mold like growth, then surface samples and air samples to determine contamination are likely to be utilized.
We don’t know what we don’t know. Samples can tell much more than what we can see with our eyes and confirm any suspect conditions. Sample testing is conducted by our accredited and experienced laboratory. The data we get from lab testing is used to confirm the suspect conditions we observe and, in some cases, to disprove a suspect condition., The more data we have, the better able we are to define the next steps to help return your property to normal.
To properly assess the indoor conditions, we must first collect an outside control, or baseline sample. This is necessary because it is important to remember that airborne mold spores are everywhere, so even a home that does not have a mold “problem” will have some mold spores within the air. For a sample to be considered “normal” it should be somewhat consistent with the outside control sample taken that at that same day and time. In general, indoor spore counts should be roughly 75% of the outdoor counts and usually proportionately similar in terms of spore types.
Sampling, done correctly, should be based on what a consultant finds during an investigation. There is no preset number of samples.
- Surface sampling is most commonly used when we observe mold like growth.
- Three most common collection methods are:
- Bulk sampling: A piece of material is extracted that may contain mold and is sent to the lab intact.
- Tape lift sampling: A specialized tape is used to lift the suspected mold like growth and is placed on a slide for laboratory analysis.
- Swab sampling uses a sanitary type of Q-Tip that is used to collect the suspected mold like growth for analysis.
- Cavity sampling is taking an air sample from an enclosed space, usually inside a wall or ceiling.
- A small hole is created, and a tube is placed within the space to collect an air sample.
- Dust sampling is used when we need to know if the surfaces or contents within a space are contaminated.
- Beneficial for use on upholstered items.
- It is frequently utilized in post-clearance inspections, especially for our CIRS protocols – for clients who are very hypersensitive to environmental hazards.
- Mold is a natural part of the outdoor environment, and it is normal for even a “clean” home to have some mold present. Mold spores are always present outside and to a lesser degree inside a home. An outside sample is how we determine what’s normal for any given day. It serves as our baseline for comparison.
- Without this baseline, you’re inspecting in the blind because outdoor conditions always fluctuate. It is the relative moldiness of indoor air that can best inform us of a home’s condition.
- It’s short for Quantitative Polymer Chain Reaction.
- The testing targets the DNA of the mold taking a deeper look at what may be
impacting a property.
- Commonly referred to as ERMI analysis when used for mold samples.
- Tests for the DNA trace of 36 different mold species to reveal their presence and
concentration levels in a home.
- Environmental Relevant Moldiness Index.
- Derived from a study done by the EPA in the early 2000s to help determine what might be baselines for
low, average, and high when completing qPCR testing.
- Known as the ERMI Score System.
- Testing scale used to determine the overall mold contamination within a building.
- Over the years, independent environmental specialists (IDPs) began to rely solely on the EMRI scores when
evaluating homes instead of looking at the other contributing factors, such as individual mold types,
concentration levels, relative humidity, etc. The ERMI score should be used as one tool in our arsenal to complete
a comprehensive investigation. When used alone, an ERMI score has much less significance in determining what
the most effective next steps should be.
- At Mold Inspection Sciences, we’ve compiled our own database, based on thousands of investigations, of average,
normal, and high, which allows us to give clients more detailed results and next steps.
- The bottom line is that qPCR data and individual mold types are invaluable data for a comprehensive
- Developed by one of the leading medical professionals in the medical end of the industry, Dr. Ritchie
- Condensed and less comprehensive version of the qPCR sample test that only tests for five different types of
molds within a home.
- Statistical data that proves when specific species of molds are present in certain concentrations. It can be used
to link the results with various health symptoms.
- Not a commonly used analysis, but can provide another data point to help in determining the concentration
level of contamination.
- Another type of qPCR testing known as the Environmental Mold and Mycotoxin Assessment.
- Tests at the DNA level for ten molds and 16 mycotoxins which are then tied to a urinalysis sample to pinpoint
whether or not exposure is happening inside the home.