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ERMI Environmental Relative Moldiness Index

Whether you are buying, selling, renting properties, or just want to ensure your present home or building does not have elevated levels of mold or toxic mold, we can provide the professional service you need.

If the answer is “yes” to any of the following questions, consider mold testing now:

  • Is there a “musty smell in your home or building?
  • Are there visible signs of water damage anywhere?
  • Has the property ever suffered a leaking basement?
  • Has the property ever suffered a roof leak?
  • Has the property ever suffered a plumbing leak?
  • Has the property ever suffered a sink or sewer overflow?
  • Has the property ever suffered other water problems?

If any of the family members, residents or occupants have experienced any of the following adverse health effects, it may indicate that mold is present in their environment.

  • sinus congestion
  • nausea
  • sneezing
  • coughing
  • skin rashes
  • flu-like symptoms
  • headaches
  • dizziness
  • irritation of the eyes, nose or throat

We perform two types of mold test:

  • Air Sampling (Non-Viable) for Mold
  • DNA sampling (ERMI Test) for Mold

Air Sampling (Non-Viable) for Mold

The process for air sampling begins by extracting at least two air samples, one from outside the property which acts as the control sample, and at least one indoor air sample which will be compared against the control sample.  For interior samples, it is recommended that 1 sample be taken for every 1,000 sq ft.. These samples are generally taken in central areas of the property.  Once the sampling is complete, these samples are taken to an accredited laboratory where they are analyzed and produce a report that identifies the mold spores detected, the concentration, and the relationship between the exterior and interior samples to determine if elevated levels of mold exist in the home.

DNA sampling (ERMI Test) for Mold

DNA sampling is commonly referred to as the ERMI test.  ERMI is the Environmental Relative Moldiness Index – the combination of EPA research, powerful PCR technology, and a new method to screen homes for mold. This test has been developed as a tool to evaluate the potential risk of indoor mold growth and associated health effects.

How Does ERMI Work?

The ERMI test involves the analysis of a single sample of dust from a property. The sample is analyzed using mold-specific quantitative polymerase chain reaction (MSQPCR), a highly specific DNA-based method for quantifying mold species. A simple algorithm is used to calculate a ratio of water damage-related species to common indoor molds and the resulting score is called the Environmental Relative Moldiness Index or ERMI. The ERMI value is typically between -10 and 20.

In order to most effectively use this new tool, the ERMI must be compared to a national database. Indices were determined using this method for 1,096 properties across the U.S. as part of the 2006 HUD American Healthy Home Survey. Individual indices, ranked from lowest to highest were used to create a national Relative Moldiness Index (RMI) Scale.

What Are The Advantages of ERMI Testing?

The ERMI test offers several advantages over traditional mold screening methods. Carpet dust acts as a reservoir for mold spores and is more representative of mold levels over time versus short-term air samples. The use of MSQPCR for this test allows for increased precision as it is based on a biochemical assay using calibrated instrumentation.

Testing Service Price
Air sampling for mold spores Starting at $375 plus hst
ERMI – Environmental Relative Moldiness Index Starting at $980 plus hst
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