Globally Harmonized System of Hazard Classification and Labeling

The Global Harmonized System of Classification and Labelling of Chemicals (GHS) addresses classification of chemicals by types of hazard and proposes harmonized hazard communication elements. These communication elements include for example the labels (pictograms and others) on pesticide products, and hazard data sheets that accompany chemical shipments. The GHS was devised to  provide a basis for harmonization of rules and regulations on chemicals at national, regional and worldwide level, an important factor to facilitate trade.

  • The GHS system proposes a harmonized system for the labeling of hazardous chemicals and is applicable to many different classifications of chemicals, including pesticides.
  • The GHS system will, if implemented correctly, provide a common basis for labeling and data sheets that will greatly facilitate safety during handling, transportation and usage that will contribute to human and environmental safety.
  • The GHS process must be science- and risk-based and not undermine existing risk-based labelling and advice to the farmer.

Governments (regulators) and industry should work together when classification and labeling is considered, to facilitate harmonization and alleviate potential trade barriers.


The GHS dates back to 1989. Following substantial review of existing national systems and endorsement through the UN Conference on the Environment and Development, Rio 1992, Chapter 19, Agenda 21, the UN Committee of Experts for the Transportation of Dangerous Goods and the Globally Harmonized Systems of Classification and Labelling of Chemicals adopted GHS in December 2002.  The system was approved by the UN in July 2003. The aim of global adoption by 2008 was over-optimistic and has not been achieved.  As of 2015 regulatory authorities in the different countries are still working on the implementation of the system.

The objective with GHS is to develop a single, globally harmonized system to address classification of chemicals, labels and safety data sheets. It aims at ensuring that information on physical hazards and toxicity from chemicals is available in order to enhance the protection of human health and the environment during the handling, transport and use of these chemicals. The GHS also provides a basis for harmonization of rules and regulations on chemicals at national, regional and worldwide level, an important factor also for trade facilitation.

The technical work on  the various issues and continuous improvement is coordinated by “The Interorganization Programme for the Sound Management of Chemicals (IOMC).  Members of the IOMC  such as OECD, ILO and UNECE work on the various technical issues such as physical hazards, health and environmental hazards as well as risk communication. Globally Harmonized System for Hazard Classification and Labelling-slide1

During the development process the following principles of harmonization provided the basic working framework for GHS development and implementation:

  • Protection afforded by the existing system will not be reduced
  • It will be based on existing systems
  • Based on their intrinsic hazards, all chemicals will be covered
  • All existing systems to change to accommodate the new system


Purpose of the GHS

The objective of the system is to establish and where necessary to improve the safety of operators dealing with chemicals as well as the protection of the environment. Chemical products are used all over the world by people who speak different languages, and who have varying literacy and education levels. Through a concise, clear and harmonized labeling and risk communication system they can all access relevant safety information.

At present, multiple labels and safety data sheets are required for the same chemical product in trade in the various markets globally. Consequently, this leads to not only higher production costs but also differences in classification and labeling. Through a harmonized system of hazard classification and labeling a uniform system for the sound management of chemicals can be established.

Classification Criteria and Risk Communication

GHS includes harmonized criteria for classifying substances and mixtures depending on their health, environmental and physical hazard levels. It also includes hazard communication elements as well as labeling and safety data sheets.  For each hazard category various labeling elements are allocated. It uses signal words such as “Danger” or “Warning”. Precautionary phrases are not yet harmonized and work to address this continues.  GHS does not intend to harmonize risk management/assessment procedures.

GHS Implementation

GHS is a non-mandatory UN treaty but it is expected that it will be implemented over time, even though the target date of 2008 has been missed.  Some countries such New Zealand have incorporated GHS into their new chemical legislation. WHO tried to align their classification system to GHS in 2009 but with only limited success.  Alignment in the EU is in progress and expected by 2015.

The Plant Science Industry and GHS