The classification of a dangerous substance or mixture is carried out, in most cases, by suppliers, i.e. self-classification.

In some cases, the decision on the classification of a hazardous chemical is taken at EU level in order to ensure adequate risk management. Member States, manufacturers, importers and downstream users may propose to harmonise the classification and labelling of a substance at European Union level. The information will also be made available in the C&L inventory.

This is usually the case for the most dangerous substances: carcinogenic, mutagenic, toxic to reproduction or respiratory sensitisers, biocidal or plant protection products.

Suppliers must label the substance or mixture inside the packaging in accordance with Regulation (EC) No 1272/2008 before placing it on the market, if:

• the substance is classified as hazardous;
• a mixture contains one or more substances classified as hazardous above a certain threshold.

The Classification and Labelling (C&L) Inventory is a database with basic information on the classification and labelling of notified and registered substances, received from manufacturers and importers. It also contains the list of mandatory harmonised classifications.