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ERMI Dust Testing

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ERMI dust Testing Finds Mold Spores in House Dust

ERMI Stands For The Environmental Relative Moldiness Index

The objective of the original ERMI dust testing research was to confirm or deny mold as a factor in asthmatic children living in homes in Boston, Kansas City, and San Diego in 2006. The testing candidates were chosen from a HUD’s 2005 American Healthy Homes Survey. Thirty six molds are included in this test. The initial results showed that Aspergillus niger was present at higher levels in children that reported “mild, intermittent asthma”.

The conclusion of the initial study found higher ERMI values were associated with homes of asthmatic children in three widely dispersed cities in the United State.

ERMI dust testing isn’t designed to see if your home has mold. The ERMI dust testing sample is a composite dust sample analyzed using ERMI protocols by a licensed environmental lab. The results are sent to the ERMI database. The ERMI database is supposed to update the ERMI results for all labs with every test. I can’t confirm that actually happens. 

Mold air and swab sampling with an onsite inspection is designed to determine if your home or office contains elevated levels of mold spores.

 Because there is such a wide variety of collection methods (the people taking the dust sample) the conclusions aren’t accurate. A trainer professional will obtain dust from a wide variety of hidden areas. A person purchasing an online ERMI test kit will sample the first dust found and usually only take dust from one or two locations. 

Different Collection Methods For ERMI Dust Sample Are The Main Problem

Here’s what I mean: Joe owns a home is the heart of Brooklyn and collects dust from under his front room couch, his 15 year old’s bedroom closet, and under his dishwasher. Jane owns a house in rural Iowa and takes a dust sample from the front seat of her work truck, on top of her refrigerator, and behind a sofa. Joe, has professional housekeeping service weekly for years. Jane is relaxed about her housekeeping and reports infrequent and/or deep cleaning. Joe’s sample probably wouldn’t have enough dust, Joe’s dust would be recent. Jane had too much dust and that dust could be 5 years old. Environmental Relative Moldiness Index, or ERMI, developed by U.S. Environmental Protection Agency researchers, is a research tool and is not recommended for use except as a research tool. There are physicians that rely on ERMI results when working with patients. We never contradict a physician and will perform ERMI testing. Homes with high ERMI values have a greater chance of having a mold problem then homes with a low ERMI. 36 different fungi make up the ERMI and are designated as Group I (those found in atypical, water-damaged homes) and Group II (those commonly found in all homes): An ERMI test is a composite dust sample test. Because of this, we cannot determine from these results where the contamination or source(s) of moisture causing any contamination are located. We also cannot give accurate cleanup instructions (remediation protocol) with this sort of sampling. Also, we are testing historical dust located in your home or office. It is not possible to determine if the dust was collected over the last five years or one week. We do try to test dust from behind the furniture or appliances, if possible. It is recommended that a companion traditional mold air samples be taken concurrently with ERMI testing. This ensures fuller snapshot in time of the mold level exposure. Because of the costs involved, we recommend obtaining mold air sample with ERMI dust samples and holding the ERMI samples at the lab, pending mold air sample results. If elevated mold spores are found in the air, then the ERMI dust samples can be analyzed at the lab. With all lab results plus our initial physical inspection with photos we are able to give mold cleanup or remediation professional instructions for successfully removing the mold from your home or office.

ERMI Dust Testing With Mold Kits

ERMI analyzed dust for mold spores. How that dust is collected, what container is used, and how the sample is shipped are important.

ERMI lab analysis is a licensed product by EPA. The ERMI test was designed to inform physicians about the living condition of a home. This will tell a physician about the day to day exposure to mold that you may experience. Keep in mind it’s a long way for mold to travel from the floor to your nose. Because ERMI measures the  normal cleanliness of your home, we can’t tell the sources of water intrusions, or how much mold growth is present from dust samples. We often take air and swab samples beside ERMI testing so that we can create a cleanup plan.


Sample ERMI Report

Environmental Testing in the San Francisco Bay Area.

American Air Testing

415-337-2923 [email protected]

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San Francisco, CA 94112