The Article 12 of the DWD is setting down rules for the “minimum requirements for treatment chemicals and filter media that come into contact with water intended for human consumption”. Member states shall organize processes and procedures to guarantee that the water quality is not affected by the materials in contact to. For this reason, treatment chemicals and filter media that come into contact with drinking water, do not:

− directly or indirectly compromise the protection of human health;

− adversely affect the colour, odour or taste of the water;

− unintentionally enhance microbial growth;

− contaminate the water at levels that are higher than necessary in view of the intended purpose.

Member States shall ensure that the purity of treatment chemicals and filter media is assessed and the quality of such chemicals and filter media is guaranteed.

Treatment chemicals and filter media positively assessed in a member state can be marketed through all European Member states.

Economic operators who produce or market treatment chemicals and filter media shall comply with the obligations set forth in the local regulations. Anyone responsible for systems for the collection, treatment, storage, supply, and distribution of drinking water shall use only authorized materials and adopt appropriate measures to prevent their contamination.

Surveillance within the national territory and the importation of treatment chemicals and filter media produced and placed on the national market should be implemented respectively by the local health authorities and by the Maritime, Air and Border Health Offices.