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Background: Globally Harmonised System (GHS)


All over the world there are different laws on how to identify the hazardous properties of chemicals (called ‘classification’) and how information about these hazards is then passed to users (through labels and safety data sheets for workers).

This can be confusing because the same chemical can have different hazard descriptions in different countries. For example, a chemical could be labelled as ‘toxic’ in one country but not in another. This also acts as a barrier to international trade.

The Earth Summit held in Rio de Janeiro in 1992 and the Word Summit held in Johannesburg in 2002 recognised this as an important global issue.

Given the expanding international market in chemical substances and mixtures, to help protect people and the environment, and to facilitate trade, the United Nations has therefore developed a ‘Globally Harmonised System’ (GHS) on classification and labelling.

The GHS is a single worldwide system for classifying and communicating the hazardous properties of industrial and consumer chemicals. GHS sits alongside the UN ‘Transport of Dangerous Goods’ system.

The UN brought together experts from different countries to create the GHS with the aim to have, worldwide, the same:

The UN GHS is not a formal treaty, but instead is a non-legally binding international agreement. Therefore countries (or trading blocks) must create local or national legislation to implement the GHS.

The CLP Regulation adopts the GHS throughout the member states of the European Union.

The UN GHS aims to ensure that information on the hazardous properties of chemicals is available throughout the world in order to enhance the protection of human health and the environment during the handling, transport and use of chemicals. GHS also provides the basis for harmonising regulations on chemicals at national, regional and worldwide level. This is important for facilitating trade. At a more basic level, GHS also aims to provide a structure for countries that do not yet have a classification and labelling system.

The UN anticipates that once fully implemented, the GHS will:

The GHS is sometimes referred to as the ‘Purple Book’ reflecting the purple binding of the published version of GHS. This is in keeping with the transport system which is often referred to as the ‘Orange Book’!

In the long run, GHS and the CLP Regulationshould make classification of mixtures easier, cheaper, more accurate, and allow for more flexibility on the part of the classifier.