GHS stands for the Globally Harmonized System of Classification and Labelling of Chemicals. GHS is a system that defines and classifies the hazards of chemical products, and communicates health and safety information on labels and material safety data sheets (called Safety Data Sheets, or SDSs, in GHS). The goal is that the same set of rules for classifying hazards, and the same format and content for labels and safety data sheets (SDS) will be adopted and used around the world. An international team of hazard communication experts developed GHS.
Currently many different countries have different systems for classification and labelling of chemical products. In addition, several different systems can exist even within the same country. This situation has been expensive for governments to regulate and enforce, costly for companies who have to comply with many different systems, and confusing for workers who need to understand the hazards of a chemical in order to work safely.
GHS promises to deliver several distinct benefits. Among them are:
The GHS system covers all hazardous chemicals and may be adopted to cover chemicals in the workplace, transport, consumer products, pesticides and pharmaceuticals. The target audiences for GHS include workers, transport workers, emergency responders and consumers.
The two major elements of GHS are:
1. Classification of the hazards of chemicals according to the GHS rules:
GHS provides guidance on classifying pure chemicals and mixtures according to its criteria or rules.
2. Communication of the hazards and precautionary information using Safety Data Sheets and labels:
Labels - With the GHS system, certain information will appear on the label. For example, the chemical identity may be required. Standardized hazard statements, signal words and symbols will appear on the label according to the classification of that chemical or mixture. Precautionary statements may also be required, if adopted by your regulatory authority.
Safety Data Sheets (SDS) - The GHS SDS has 16 sections in a set order, and minimum information is prescribed.
Within the GHS classification system, there are three major hazard groups:
Within each of these hazard groups there are classes and categories. Each of these parts is called a building block. Each country can determine which building blocks of the GHS system it will use in their different sectors (workplace, transportation, consumers). Once the building blocks are chosen, the corresponding GHS rules for classification and labels must be used.
Criteria for classifying chemicals have been developed for the following health hazard classes:
In addition, there are specific classification rules for chemical mixtures for each health hazard class.
Criteria for classifying chemicals have been developed for the following physical hazard classes:
Criteria for classifying chemicals have been developed for the following environmental hazard class:
In addition, there are specific classification rules for chemical mixtures for each environmental hazard class.
The most current information on GHS classification, labels and SDS as well as other criteria is available in the 4th revised edition* of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)from the United Nations Economic Commission for Europe (UNECE).
GHS is a dynamic system. The international GHS committee meets twice a year to work on developing potential new hazard classes as well as resolving specific issues, and updating the latest GHS publication. Check the above link for more information.
*However, note that countries can (and have) implemented different versions of GHS. For example, the US HazCom 2012 legislation is based on the 3rd revised edition. It is anticipated that Canada will also adopt the 3rd revised edition to harmonize with the US.
Countries and sectors (consumer, environmental, workplace, transportation) within a country will implement GHS at varying times depending on their local circumstances.
The Globally Harmonized System for Classification and Labelling of Chemicals (GHS) is being implemented by Canada and this alignment will change WHMIS-related laws (the Hazardous Products Act and Controlled Products Regulations).
Health Canada is the government body responsible for making the required changes to the WHMIS related laws. They have indicated that draft regulations will be proposed in Spring 2013, with final regulations published in early 2014. Health Canada’s goal is to have the updated WHMIS laws in force by June 2015. In force means that suppliers may begin to use and follow the new requirements for labels and SDSs for hazardous products sold, distributed, or imported into Canada at that time. A transition period is expected, but the dates have not yet been announced.
Provincial and territorial WHMIS regulations will also require updating. It is expected that jurisdictions will complete this update by June 2016. Employers will be expected to have updated their WHMIS program and training to include the alignment with GHS at this time (exact timelines to be determined).
GHS has been adopted into the new EU Classification, Labelling and Packaging (CLP) regulations (in force as of January 20, 2009). These regulations must be used for new products which are:
There is a two-year transition period for existing products labelled and packaged according to EU Directives (67/548/EEC and 1999/45/EC, both as amended).
Final Rule became effective May 26, 2012. Key dates in the US implementation include:
Adapted from: Hazard Communication Standard Final Rule, OSHA Fact Sheet (2012)
To find out more about the status of GHS implementation in other countries and their sectors please see the article produced by the UNECE.
It is very likely. GHS is expected to be implemented by other regulatory agencies, including by Transport Canada for the Transport of Dangerous Goods, and by Health Canada for Consumer Chemical Products and Pest Control Products. Discussions are occurring but the consultations are not complete.
For more information see the page Globally Harmonized System of Classification and Labelling of Chemicals (GHS) on the Health Canada web site.
Overall, the current roles and responsibilities for suppliers, employers and workers likely will not change in WHMIS after GHS.
Suppliers, Importers and Producers duties will continue to include:
Employers must continue to:
Workers will still:
How chemicals are classified will be affected. It is likely (but not confirmed) that WHMIS legislation will:
Labels requirements will also change, and will probably have a few new requirements. Labels will use new pictograms, as well as a signal word - Warning or Danger.

Under the GHS system, once a chemical is classified, specific signal words, hazard statements and pictograms are required (prescribed) for each hazard class and category. These elements must appear on the label.
All of the required elements for labels are not yet determined. It is still not clear, for example, if the names of hazardous ingredients will be included on the label, or if the WHMIS hatched border will still be required.
NOTE that currently in Canada, GHS labels do not meet WHMIS requirements. Employers should contact suppliers to request WHMIS labels if the WHMIS version of a label is not supplied with the product.
SDSs will use a 16-section format. There will be standardized information requirements for each section. The 9-section WHMIS format for MSDSs will no longer be acceptable. Another important change to note is that the product classification and some of the label information will probably be required on the SDS. It has not been determined if the SDS updating requirements (every 3 years) will be kept; however, SDSs must be updated as new information comes available.
NOTE that Health Canada has announced an administrative policy which allows a properly prepared and formatted GHS Safety Data Sheet (SDS) to be used in Canada at this time. All of the information required by the 9-section Canadian MSDS must be listed on the GHS SDS.
Specific information on this administrative policy can be found at the following web page from Health Canada:
Material safety data sheets - Format
The information requirements of Canadian 9-heading SDS (Schedule I, Column III of the Controlled Products Regulation) can be found here:
CPR Schedule I - Information to be Disclosed on a Material Safety Data Sheet
Note that there are additional Canadian requirements for MSDSs/SDSs which must continue to be met at this time, for example:
Under WHMIS after GHS, suppliers will continue to classify products, create labels and create SDSs (formerly MSDSs) but they will follow the WHMIS after GHS requirements.
To prepare to classify a product, suppliers could:
Once changes to WHMIS legislation have been published, confirm product classifications.
Suppliers must use a weight of evidence approach to classify products. The validity of research reports and other information must be evaluated as a whole. In some cases a single, well-conducted study will be sufficient.
If they are not already doing so, suppliers could also switch to a 16-section SDS format.
After GHS implementation, SDSs and labels for products originating within and outside of Canada will share common elements. This standardization should simplify education and training after the transition period is over. However employees will need training on both systems until the transition is complete.
Keeping up-to-date inventories of all controlled products and the status of the MSDS/SDS will be essential.
The Canadian Centre for Occupational Health and Safety (CCOHS), in partnership with Health Canada, has developed and released two free on-line training courses to help workplaces prepare for WHMIS After GHS.
These free courses provide an introduction to the expected changes to WHMIS after GHS. Participants will learn about the expected impacts of these changes for workers, employers, and chemical suppliers.
WHMIS After GHS: An Introduction (30 minutes)
WHMIS After GHS: How Suppliers Can Prepare (60 minutes)
Both courses are offered in English and French, and are free of charge but registration is required in order to keep users aware of changes to the courses.
Health Canada also offers an email news service to announce information about WHMIS.
Document last updated on February 19, 2013
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