A distinction is made between two different evaluation processes: the so-called "dossier evaluation" and the "substance evaluation". The difference between the two processes lies in their differing areas of responsibility.
Dossier evaluation primarily serves to ensure the quality of the data and to avoid unnecessary animal testing. The central European Chemicals Agency (ECHA) is responsible for dossier evaluation. On the one hand, ECHA examines all submitted testing proposals. In particular, it reviews whether the testing proposals meet the requirements of the REACH Regulation and whether – in the case of multiple registrants – animal testing, for example, can be avoided. Secondly, ECHA reviews the submitted documents for completeness and plausibility. The aim is for ECHA to subject at least five percent of the registration dossiers from each tonnage threshold to such a plausibility check.
If any suspicion of a corresponding risk to human health or the environment arises, a substance can be reviewed regardless of the tonnage. Where applicable, appropriate test data is requested from the companies. The substance evaluation is carried out by the national agencies of the member states. In cooperation with ECHA, a list is prepared of substances that are to be subjected to substance evaluation.