Any GUT-PRODIS certified product only uses aluminium oxide hydrate (ATH) as a flame retardant. ATH is an inorganic mineral which contains water which is then released when exposed to high temperatures. The water cools the flame and prevents the spread of the fire. Due to its chemical structure, ATH is harmless and is usually incorporated as a functional filler within the adhesive layer between the face and the backing of the textile floor covering.

Over time, GUT has developed a list of flame retardants which are prohibited for use during the manufacture of textile floor coverings. This is to ensure that any carpets produced conform to the desired standards on flame retardancy whilst not using any  substances which are damaging to the consumer or the environment.  The following list is an overview of the banned substances.

Flame retardants are used to prevent the development of a fire and inhibit the spread of flame once a fire has started. Flare retardants made of different compounds are added to many items in daily use, for example upholstered furniture in vehicles, home textiles and electrical appliances. In these instances, brominated and chlorinated organic compounds are the most effective, however, they are harmful to the environment. It is therefore important to be certain that the benefits of using these materials outweighs the potential harm.

Textile floor coverings which are installed ‘wall-to-wall’ are considered to be construction products and therefore regulated across the EU by the Construction Products Regulation (CPR). The corresponding requirements can be found in the harmonised standard EN 14041. If a flame retardant has to be used so that a product complies with a certain fire class, an annual inspection must be carried out by an independently certified third party. The CE Marking framework documents this information.

Building materials are generally classified according to their fire behaviour, and the tests which determine the level of fire protection are as follows:

• non-flammable
• flame-retardant
• normal flammability
• inflammable

The European standard EN 13501-1 grades floor coverings further and creates classifications according to the level of combustion: for example, A is non-combustible and F is highly flammable. Textile floor coverings are also marked with the abbreviation "fl" and are mainly classified as B-fl, C-fl and E-fl. B-fl is the most stringent fire classification for a textile floor covering and is only required in areas with special requirements such as fire escape routes in hotels, or specific rooms in public buildings and offices. In most cases within the private sector, E-fl is usually sufficient. Easily recognisable pictograms are used to indicate the classification on different products.

Textile floor coverings are tested in situ (ie they are tested once they have been installed), therefore the type of installation method and subfloor has to be noted. These then appear on the pictograms as letters or abbreviations to indicate how the test results were achieved.

In addition to the halogenated flame retardants (ie those which contain bromine and chlorine compounds), there are also those which contain phosphorous, nitrogen (based on melamine) or borates. However, by far the largest group of flame retardants are inorganic compounds which, due to their structure and composition, release water at elevated temperatures. These include ATH (aluminium trihydroxide) and MDH (magnesium dihydroxide).

Nearly 80% of textile floor coverings in the private sector do not have additional flame retardants added, whilst within the commercial sector, with its higher statutory requirements, approximately 43% have no additional flame retardants. This proves that textile floor coverings can be produced safely and without the need for additional chemicals to be used in order to achieve the required National and European fire regulations, providing the correct materials are selected for the correct construction in manufacture. In those cases where the use of flame retardants is needed to guarantee additional safety requirements only those substances that are not prohibited are allowed to be used. In most case ATH (aluminium trihydroxide) is use.