Standard & approval

EN 16421 (W270)

Influence of materials on drinking water, enhancement of microbial growth (formerly W270)

The influence of materials on water intended for human consumption, specifically the enhancement of microbial growth.

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Field

Drinking water

Focus

Microorganisms

formerly

W270

Applies to

Seals in drinking water

Overview

EN 16421 (formerly W270) governs how materials in contact with drinking water influence the growth of microorganisms. On request, we supply seals made of materials with the corresponding approval or conformity.

EN 16421 replaces the DVGW worksheet W 270 (often referred to as DVGW W270). For drinking water seals we recommend our EPDM blue material. Further requirements for materials in contact with drinking water are set out in the KTW-BWGL and the DVGW approval. An overview is given under drinking water.

FAQ

The key questions

What does the EN 16421 standard cover?

Water intended for human consumption comes into contact with construction products during storage, transport and distribution. Materials are selected on the basis of technical requirements in order to control their influence on water quality, such as the release of substances and effects on odour, taste or colour. The standard also determines whether materials promote the growth of microorganisms. All of these points are laid down in EN 16421 (formerly W270).

Which requirements must be met?

In Germany, the requirements for the quality of drinking water are laid down in the Drinking Water Ordinance (TrinkwV). We help to ensure that only suitable and approved materials are used for drinking water contact in the sanitary sector.

Which products require EN 16421 approval?

All seals used with water intended for human consumption, particularly with regard to the growth of microorganisms, for example for fittings and piping systems.

How do products obtain EN 16421 approval?

Some of our materials already hold an official EN 16421 (formerly W270) approval or conformity, both as sheet material for punched parts and flat seals and for moulded articles, sealing rings, hose rings and O-rings.

What are the benefits of EN 16421?

The standard governs the growth of microorganisms in water intended for human consumption and represents a compromise between the established practices of the member states.

Applications