General health information:

Formaldehyde

For a healthier indoor environment

General health information: formaldehyde

Formaldehyde is a volatile organic compound (VOC) with distinctive properties. It belongs to the aldehyde group and is a toxic, colourless, flammable gas with a sharp, acidic odour. It is highly soluble in water and alcohol. A 37% solution in water is sold commercially as formalin.

At elevated concentrations in indoor air, formaldehyde can cause allergic reactions or irritate the skin, airways or eyes. The concentration at which symptoms occur varies from person to person.

Formaldehyde is rarely added directly to products used indoors. It is usually released when adhesives or binders react with moisture in the air. The main potential indoor sources are:

Bonded products made of wood-based materials, cork boards and similar materials (adhesives that release formaldehyde)
Insulation and foam fillers (urea-formaldehyde foams)
Coatings, paints, varnishes and parquet sealers (formaldehyde in preservatives or binders)
Glass wool, stone wool and fibre mats (binders containing formaldehyde)
Textiles and textile floor coverings (finishes containing urea-formaldehyde resins)

Historically, emissions from chipboard were the main source of indoor formaldehyde. The F0, E1, E2 and E3 emission classes were defined for chipboard as follows:

Class F0

The wood-based material contains no formaldehyde. The alternative binder contains bound isocyanates, which are considered harmless in their bound form but can pose problems during manufacture and processing.

Class E1

Under specified conditions, the material does not produce an indoor air concentration above 0.1 ppm of formaldehyde.

Class E2

Under specified conditions, the material does not produce an indoor air concentration above 1.0 ppm of formaldehyde.

Class E3

Under specified conditions, the material does not produce an indoor air concentration above 1.4 ppm of formaldehyde.

The German requirements described here restrict wood-based materials for interior fit-outs to emission classes F0 and E1, with the aim of keeping indoor concentrations below 124 µg/m³ (0.1 ppm).

Sampling and analysis

Indoor air is sampled for formaldehyde by active collection on DNPH cartridges, in accordance with ISO 16000 Part 3 and DIN EN ISO 16000 Part 1. Long-term passive sampling using Radiello® samplers is also possible. After solvent elution, samples are analysed by high-performance liquid chromatography (HPLC).

Formaldehyde assessment criteria

In 2004, the International Agency for Research on Cancer (IARC), part of the World Health Organisation (WHO), classified formaldehyde as carcinogenic to humans. Substances classified as carcinogenic, mutagenic or toxic to reproduction (CMR) are particularly hazardous and should be replaced with less hazardous alternatives. Germany’s Federal Institute for Risk Assessment (BfR) subsequently also classified formaldehyde as carcinogenic to humans. The former German Federal Health Office published a guideline value of 124 µg/m³ (0.1 ppm). The article records a WHO precautionary value of 60 µg/m³, approximately the average concentration reported in German indoor environments at the time.

Note: Certification confirms that a product met the requirements of the applicable testing programme at the time of testing. It does not provide a comprehensive assessment of a product’s suitability for health or of the health effects of an entire indoor environment.