INTERPRETATION CRITERIA

Interpretation criteria are available for differentiating surfaces containing mould growth from those containing deposited spores as on a dusty surface, and for defining clean as the success criteria for the cleaning of surfaces.

Interpretation criteria is also available for measuring inside porous materials such as insulation materials (glass wool, mineral wool, ceiling tiles and other) and in cement containing materials (mortar, some types of concrete). The criteria allow differentiation of contaminated materials (containing mould growth) from non-contaminated materials.

Data has been collected from hundreds of samples to establish the interpretation criteria. These categories of surface contamination were developed as a result of testing performed in collaboration with the Danish Building Research Institute and the Technical University of Denmark.

Criteria for Mycometer surface

Samples collected on a 9 cm2 area and analysed according to the Mycometer surface protocol.

Category A: The Mycometer surface (MMS)-value ≤ 25 FLU.
The level of mould is not above normal background level. Success criteria for the cleaning of surfaces that were contaminated with mould growth.

Category B: 25 < The MMS-value ≤ 450 FLU.
The level of mould is above normal background level. This is typically due to high concentrations of spores and hyphal fragments in dust deposits but may in some cases indicate the presence of old mould damage (mould growth).

Category C: The rMMS-value > 450 FLU.
The level of mould is high, above normal background levels, due to mould growth on the surface.

FLU = Fluorescense Units

Criteria for analysis of mould growth inside insulation materials

100 mg samples analysed according to the Mycometer protocol on insulation materials.

Category A: The Mycometer-value ≤ 150 FLU.
The level of mould is not above normal background level seen in relatively new insulation materials.

Category B: 150 < The Mycometer-value ≤ 450 FLU.
The level of mould is above normal background level. This is typically due to high concentrations of spores in dust deposits.

Category C: The Mycometer-value > 450 FLU.
The level of mould is high, above normal background levels,due to mould in the insulation material.

FLU = Fluorescense Units

Criteria for analysis of mould growth inside cement containing materials

300 mg samples analysed according to the Mycometer protocol on cement containing materials (mortar and different types of concrete.

Category A: The Mycometer-value ≤ 60 FLU.
The level of mould is not above normal background level.

Category B: 60 < The Mycometer-value ≤ 200 FLU.
The level of mould inside the material is above normal background level. Category B level results is indicative of a slight mould contamination, likely depositied fungal debris, which can often be found in older Mortar/Concrete materials.

Category C: The Mycometer-value > 200 FLU.
The level of mould inside the material is high above normal background levels due to mould growth.

FLU = Fluorescense Units

Mycometer-surface Applications

  • Post remediation verification (PRV)
  • Documenting the efficacy of the cleaning of surfaces for mould growth
  • Documentation of mould growth
  • Documentation that discoloration is NOT mould growth
  • Delineation of mould growth where it is non-visible. How much should be cleaned?
  • Documenting the cleaning of HVAC systems