To ensure that an object is capable to come into contact with foods, it is necessary to check if materials which constitute it, and coming into contact with foods, meets the requirements of inertness. The list of materials concerned is in the Regulation CE n° 1935/2004 from 27/10/04. The inertness criteria applicable are different depending on the chemical nature of the materials. Generally, the requirements concern :
- the composition of materials,
- the migration thresholds in the foods of the substances used to process the materials,
- the absence of deterioration, by materials, of food's sensory properties.
Specific criteria apply to materials which are subject to treatments (ionizing, recycling), and also to colorants and cleaners of materials coming into contact with foods.