Mould FAQ

Frequently Asked Questions (FAQ) about Mould

Mould Detection, Mould Inspection and Mould Testing

What is Mould? 

Mould is a type of fungus that is a natural decomposer of organic material. Mould spores are located everywhere in the air. It only starts to grow when it comes into contact with a water source such as moisture, humidity, or condensation.

Why mould is bad for you?

Mould is bad for you because it produces mould spores, which are inhalable and aggravate asthma. Mould can also cause some people to sneeze or cough. Mould may also produce mycotoxins, which can be found on mould spores. These mycotoxins can enter the body and cause mould illness or biotoxin illness. This results in symptoms such as chronic fatigue and chronic inflammation.

Are there mould testing kits?

There are many ways to test for mould. However, each test is looking for different things. Buying a mould testing kit does not determine the root cause of the mould growth. Therefore, mould testing kits are not recommended. However, there are 2 types of testing kits that can be recommended. This is an ERMI or HERTSMI Test. 

A building biologist will typically use air and surface sampling tests amongst other environmental measurements to detect where mould is growing. Sometimes, mould growth is hidden. 

What is an ERMI or HERTSMI Test?

What is an ERMI Test?

The US Department of Housing and Urban Development developed the Environmental Relative Moldiness Index (ERMI) in 2006 to provide a way to quantify the “relative mould-burden” in homes anywhere in the country. It is used as an index on a scale of 0 to 100, with higher values indicating higher levels of mould.

The ERMI system can identify both the genus and species of fungi present in an area with high levels of water damage. The 36 indicator species that makeup ERMI were chosen because they can typically be found at relatively high concentrations in homes throughout the United States.

The ERMI test checks for mould in dust, which is everywhere. This test is expensive and can cost up to $400.

Patients with Chronic Inflammatory Response Syndrome (CIRS) should get an ERMI relative mouldiness Index of < 2. 

If the ERMI relative mouldiness Index is > 5, then hire a Building Biologist to do Mould Inspection and Mould Testing.

What is a HERTSMI Test?

HERTSMI is a cheaper mould test than ERMI. The presence of ANY of the five pathogenic fungi detected will be given a score.

  1. Aspergillus penicilloides
  2. Aspergillus versicolor
  3. Chaetomium globosum
  4. Stachybotrys chartarum
  5. Wallemia sebi

A HERTSMI score >11 should consider hiring a Building Biologist to do Mould Inspection and Mould Testing.