Skip to main content

Historical background

Globally Harmonized System of Classification and Labelling of Chemicals (GHS)

The work about the elaboration of the GHS began with the premise that existing systems should be harmonized in order to develop a single, globally harmonized system to address classification of chemicals, labels, and safety data sheets. This was not a totally novel concept since harmonization of classification and labelling was already largely in place for physical hazards and acute toxicity in the transport sector, based on the work of the United Nations Economic and Social Council's Committee of Experts on the Transport of Dangerous Goods (UNCEDTG). Harmonization had not been achieved in the workplace or consumer sectors, however, and transport requirements in countries were often not harmonized with those of other sectors in that country.
Chapter 19 of Agenda 21, adopted at the United Nations Conference on Environment and Development (UNCED, 1992), provided the international mandate to complete this task. The work was coordinated and managed under the auspices of the Interorganization Programme for the Sound Management of Chemicals (IOMC) Coordinating Group for the Harmonization of Chemical Classification Systems (CG/HCCS). The technical focal points for completing the work were:


It required a long-term commitment from all of these organizations that they maintained over the years. By resolution 1999/65 of 26 October 1999 the United Nations Economic and Social Council decided to enlarge the mandate of the Committee of Experts on the Transport of Dangerous Goods by reconfiguring it into a Committee of Experts on the Transport of Dangerous Goods and on the Globally Harmonized System of Classification and Labelling of Chemicals (CETDGGHS), and by creating, besides the Sub-Committee of Experts on the Transport of Dangerous Goods (TDG Sub-Committee), a new Sub-Committee of Experts on the Globally Harmonized System of Classification and Labelling of Chemicals (GHS Sub-Committee).
The GHS Sub-Committee is responsible for maintaining the GHS, promoting its implementation and providing additional guidance as needs arise, while maintaining stability in the system to encourage its adoption. Under its auspices, the GHS is regularly revised and updated to reflect national, regional and international experiences in implementing its requirements into national, regional and international laws, as well as the experiences of those doing the classification and labelling.

The first task of the GHS Sub-Committee was to make the GHS available for worldwide use and application. The first edition of the GHS, which was intended to serve as the initial basis for the global implementation of the system, was adopted in December 2002. Since then, the GHS has been updated every two years. 

At its tenth session (11 December 2020), the Committee adopted a set of amendments to the eighth revised edition of the GHS which include, inter alia, the revision of chapter 2.1 (explosives) to better address their explosion hazard when they are not in their transport configuration; the revision of decision logics, and the classification and labelling summary tables in Annex 1; the revision and further rationalization of precautionary statements and the updating of references to OECD test guidelines for the testing of chemicals in annexes 9 and 10. The ninth revised edition of the GHS (GHS Rev.9), to be published in 2021, will take account of these amendments which were circulated as document ST/SG/AC.10/48/Add.3.

The System is ready for worldwide implementation. In its Plan of Implementation (para 22.(c)) adopted in Johannesburg on 4 September 2002, the World Summit on Sustainable Development (WSSD) encouraged countries to implement the new GHS as soon as possible. Information about the status of implementation of the GHS by country is available (in English only) in the page following the link "GHS implementation and guidance" on the left hand menu.