Emission Classification of Building Materials

Products tested in accordance with the M1 criteria

• An M1-classified product has been tested in accordance with the M1 Classification requirements and meets the M1 criteria for chemical emissions into indoor air and odour acceptability.
• In addition to the chemical emission criteria, the M1 Classification requires the product’s odour to meet the applicable acceptability criterion.
• The M1 Classification differs from several other European emission classifications by assessing ammonia emissions and odour acceptability in addition to VOC and formaldehyde emissions.
• The use of materials that meet the M1 criteria helps to manage material-related chemical emissions. However, it does not replace the appropriate design, implementation and operation of structures, ventilation and other factors affecting the indoor environment.

An M1-classified product meets the M1 criteria for chemical emissions into indoor air.

The M1 Classification focuses on emissions released from building materials and furniture into indoor air. It sets limit values for emissions of volatile organic compounds (VOC), formaldehyde and ammonia, as well as a criterion for odour acceptability.

The M1 Classification sets criteria for long-term emissions, also referred to as product-specific emission rates, to assess material-related chemical emissions during the use of a building. The classification does not include criteria for primary emissions that decrease rapidly, such as emissions from solvents and other auxiliary substances during drying and film formation. Therefore, emission measurements required by the M1 Classification are carried out after an ageing period of 28 days, except for office chairs, which are tested after three days.

The classification system is based on multidisciplinary expertise and impartiality

The Emission Classification of Building Materials is owned by The Building Information Foundation RTS sr and operated by The Building Information Foundation RTS’s subsidiary Rakennustieto Oy. The classification is overseen and developed by the principal committee Indoor Environment (PT 41) appointed by The Building Information Foundation RTS, in which representatives include construction products industry, developers, designers, and research institutes. Classification applications and matters related to classification decisions are handled confidentially by a separate impartial classification committee.  

The voluntary M1 Classification for building materials is part of the broader Classification of Indoor Environment (Sisäilmastoluokitus) developed by the Finnish Society of Indoor Air Quality and Climate (Sisäilmayhdistys ry) and Building Information Foundation, RTS (Rakennustietosäätiö, RTS).  The Classification of Indoor Environment is used by architects, designers, contractors, and manufacturers when building healthier and more comfortable buildings.

The classification decisions are based on the document Classification of Indoor Environment 2018 (Sisäilmastoluokitus 2018), the general rules of the classification and the classification criteria.

M1 is a Finnish emission classification used internationally

In Finland, testing chemical emissions released from building materials and furniture into indoor air is not generally required by law. The voluntary M1 Classification provides a method for assessing these emissions and the acceptability of the product’s odour. The purpose of the classification is to promote the consideration of material-related chemical emissions as part of the design and implementation of a good indoor environment.

The M1 Classification assesses emissions of volatile organic compounds (VOC), formaldehyde and ammonia, as well as the acceptability of the product’s odour. M1 criteria and limit values have been established for these properties.

The M1 Classification is used in Finland and internationally to demonstrate the emission properties of building materials and furniture. An M1-classified product meets the M1 criteria for chemical emissions into indoor air and odour acceptability.

The assessed properties, testing conditions, measurement times and calculation methods may differ between emission classification systems. Therefore, the limit values and measurement results of different classifications should not be compared without considering the applicable testing and calculation methods.

M1 limit value examination helps to demonstrate that your products comply with the EU taxonomy regarding emissions.

According to the EU taxonomy, building materials must fulfill certain requirements to be classified as environmentally sustainable. These requirements include restrictions on emissions of carcinogenic, mutagenic, and reprotoxic (CMR) compounds, as well as formaldehyde emissions.

This means that manufacturers and suppliers of building materials must ensure that their products meet these requirements before being placed on the market. The EU taxonomy limit values apply to both the construction of new buildings and the renovation or renewal of existing buildings. The M1 limit value examination is an additional service of the M1 Classification, which is recommended for all products that are intended to be used inside the vapor barrier.

M1-classified product supports the objectives of EU taxonomy

It is possible to combine the M1 Classification with a limit value examination of building material emissions for the purpose of verifying compliance with the indoor air emission criteria of the EU Taxonomy or SINTEF approval.

Depending on the intended use, the limit value examination can have two different scopes:

1.    emission of formaldehyde < 60 μg/m³ and emissions of carcinogenic compounds < 1 μg/m³ (scope required for taxonomy reporting)

2.    emission of formaldehyde < 60 μg/m³, emissions of carcinogenic compounds < 1 μg/m³, and total volatile organic compound (TVOC) < 300 μg/m³ (scope suitable for taxonomy and SINTEF)

In principle, all emission test reports for products with valid M1 Classification are usable for the limit value examination. The limit value examination can be ordered both as part of the normal classification process as well as during an ongoing classification period.

The result of the limit value examination is included in the M1 certificate of the product or product group. The certificate:

• demonstrates that the product or product group is M1-classified and meets the M1 criteria for chemical emissions into indoor air and odour acceptability
• presents the emission data assessed in the limit value examination in a standardised format for EU Taxonomy reporting
• contains information on the product’s chemical emissions assessed by an independent third party
• brings together the information required for reporting in a single certificate, meaning that separate test reports generally do not need to be provided for reporting purposes.