Different systems of classification and labelling (C&L) of chemicals are currently used throughout the world. The same substance may be classified as “toxic” in the United States, “harmful” in the European Union and “not dangerous” in China. To eliminate these disparities and to reinforce protection for people and the environment in all countries, it was decided to develop a Globally Harmonised classification and labelling System (GHS) under the aegis of the United Nations. The GHS was formally adopted in 2002 by the United Nations Economic and Social Committee (UN ECOSOC) and revised in 2005 and 2007.
It aims to improve the communication on hazards for workers, consumers, emergency responders and in transport, via harmonised labels and where relevant, harmonised safety data sheets.

GHS implementation in EU

The GHS is a set of international recommendations. Therefore its application is an opt-in one. But, like most countries, the European Union has chosen to make it mandatory by bringing it into Community law.
The GHS relevant criteria are thus totally included in the EU transport legislation in 2009. Concerning supply and use of chemicals, the European Commission adopted in late 2008 the so called "CLP" regulation (EC) No 1272/2008 on classification, labelling and packaging of hazardous substances and mixtures, which will replace in the medium term the current system.
This regulation takes into account the classification criteria and labelling rules of the GHS but it is also built on the 40 years of experience obtained through implementation of existing Community chemicals legislation. The achieved level of protection is maintained through Community hazard classes not yet part of the GHS and by keeping some current classification and labelling rules. Moreover, all hazard classes of the GHS have been taken over by the regulation, but certain categories (levels of hazard severity inside a class), not part of current legislation, are not included. The CLP regulation incorporates some hazard classes or categories which are not present in current EU legislation for supply and use, but are – or will be – part of the EU transport system.

Consistency with REACH

The CLP regulation includes the necessary amendments to be made to REACH and certain REACH provisions are transferred to it:

1. obligation for companies to classify their substances and mixtures themselves and to notify the classifications;
2. a harmonised list of substances classified at Community level will be drawn up;
3. a classification and labelling inventory, made up of all notifications and harmonised classifications referred to above, will be established.

As safety data sheets are the main tool for communication under the REACH regulation, the provisions on safety data sheets remain there.

The main changes introduced by the CLP regulation

The regulation follows the GHS terminology: the term “substance” is kept but “preparation” is replaced by “mixture”; the term “category of danger” is replaced by “hazard class”. Hazard class means the nature of the physical, health or environmental hazard. Certain hazard classes may comprise differentiations; other classes may include hazard categories.
The CLP regulation defines 28 hazard classes: 16 physical hazard classes, 10 health hazard classes, one environmental hazard class and an additional class for substances hazardous for the ozone layer. Classes based on physico-chemical properties are different from the current categories of danger. They are built on classes defined in the international legislation concerning the transport of dangerous goods. Certain classes are therefore not known by the European users. On the other hand, the health hazards are similar to the hazards defined by the current system even if they are organized and allocated differently inside the hazard classes.

Classification criteria of the two systems, i.e. rules used to define that a chemical belongs to a hazard class and to a category within this class, may differ. In addition, changes of cut-off values and calculation methods for mixtures will probably lead to more chemicals being classified under the new system.

Labelling under the regulation includes elements which, for most of them, are different from those currently used in the workplace in Europe. Required information is the product identifiers, supplier identity, hazard pictograms, signal words, hazard statements and precautionary statements.

For more information, see the label elements for physical hazards, health hazards and environmental hazards.

Transition between the two systems

The regulation provides for the coexistence of the current and CLP systems during a transitional period. By 1 December 2010, substance labels will have to be drawn up in accordance with the new CLP system but the classification under the current system will still have to be mentioned in the safety data sheet with the new one. Up to 1 June 2015, companies in charge of chemicals labelling are free to use one of the two systems for mixtures. If the new system is chosen, the label will have to be prepared in accordance with it but the two classifications will have to be given in the safety data sheet. From 1 June 2015 onwards, the current directives will be repealed and completely replaced by the CLP regulation.