How to correctly identify chemicals on the CLP labels?

What is a product identifier?

The product identifier is the information on a chemical label that enables the identification of a substance or mixture. The content of the product identifier is specified in Article 18 of the CLP Regulation. Its format depends on whether we are dealing with:

• a substance – the name and identification number in accordance with Annex VI to the CLP Regulation (if the substance is listed there) must be provided; in other cases, a name and ID number from the C&L Inventory may be used or, further, the CAS number if the substance is not listed in any of the above;

• a mixture – the trade name or product designation must be provided, and the mixture components that lead to its classification in the following hazard classes must be indicated: acute toxicity, skin corrosion or serious eye damage, germ cell mutagenicity, carcinogenicity, reproductive toxicity, skin or respiratory sensitisation, specific target organ toxicity (STOT), or aspiration hazard.

What information must the product identifier include?

On chemical product labels, the product identifier should include:

🔹 The name of the substance or mixture

🔹 For substances – the index number (if applicable) or another identification number, such as the CAS number

🔹 For mixtures – information about the mixture components contributing to classification in specific hazard classes (where applicable)

For mixtures, the product identifier must be defined precisely to ensure that the appropriate substances affecting classification are clearly indicated.

What to keep in mind when it comes to the product identifier?

🔧 If you manufacture or import a chemical substance, ensure that:

• the name on the label matches the one in section 1.1 of the safety data sheet (SDS),

• the correct identifying number and appropriate chemical name are shown on the label – remember the hierarchy of available sources.

🔧 If you manufacture or import a chemical mixture, ensure that:

• the name on the label matches the one in section 1.1 of the safety data sheet (SDS),

• the ingredients contributing to the product’s classification are selected and listed in accordance with the CLP Regulation.

Common mistakes on CLP labels regarding the product identifier

❌ Missing CAS number or incorrect identifier chosen contrary to the required hierarchy

❌ Omission of key mixture components

❌ Discrepancies between the label and the safety data sheet

Summary

Chemical product labels must include a correct product identifier, in compliance with the requirements of the CLP Regulation. Although this may seem like an obvious part of the labelling process, there are rules that govern how chemical substances and mixtures should be identified under CLP.