Classifying workplace hazardous chemicals

The model Work Health and Safety Regulations (WHS Regulations) impose a duty on manufacturers and importers of chemicals supplied to a workplace to determine if a chemical is hazardous, and to correctly classify the chemical according to the 3rd Revised Edition of the Globally Harmonised System of Classification and Labelling of Chemicals (GHS).

Note: The tables in Schedule 6 of the WHS Regulations replace some tables of the GHS. This relates to cut-off concentrations for some hazard categories. 

Note: Some GHS hazard classes and categories are not covered by the WHS Regulations. Refer to the definition of hazardous chemical in the WHS Regulations for more information. 

The hazard classification of a chemical determines what information must be included on labels and Safety Data Sheets to comply with the WHS Regulations. If the classification of a hazardous chemicals changes or new information comes to light, the label and SDS must be reviewed and revised.

The WHS Regulations provide transitional arrangements to allow existing chemicals to be classified according to the GHS over a 5 year period. During this 5 year period, either the GHS or the NOHSC classification system may be used.

How to Classify Workplace Hazardous Chemicals

Chemicals may be classified from “first principles”, which means using the raw test data for the chemical and applying the criteria.  There are four basic steps to classifying a substance, mixture or article in this way:

• Collect all available information,
• Evaluate the adequacy and reliability of the information,
• Review the information against the classification criteria, and
• Make a determination on its classification.

These steps can be used regardless of which classification system is used. 

Alternatively, for existing chemicals with a known hazard classification under the old system, a GHS classification can be derived by simple translation in most cases.  The following document provides useful guidance on translating existing classifications into the GHS. 

• Guidance on requirements for classification of hazardous chemicals under the WHS regulations

Translation Tool

The following electronic resource is freely available and allows classifiers to input existing classification information to determine a classification under the GHS. 

• GHS converter (BRCI)

Note: due to slight variations in how individual countries are implementing the GHS the classification determined using these tools may not be completely accurate for Australian WHS regulatory purposes (for example some hazard categories may be regulated in Australia but not in Europe and vice versa). 

Lists of classified substances

Lists of classified substances like the <<Hazardous Substances Information System>> are non-mandatory under the WHS Regulations, and should be used as guidance only. It is the classification criteria themselves that are mandatory. 

There are many sources of information on chemical hazard classification available both nationally and internationally, for both the current classification system and the GHS. Some key links are provided below. 

GHS classification information

• European Commission CLP Regulations Annex VI table 3.1 – contains a list of more than 4000 GHS-classified chemical substances

Hazardous substances

• HSIS – contains a list of hazardous substances classified according to the Approved Criteria

Dangerous goods

• ADG Code 7th Edition – contains a list of substances, mixtures and articles classified as dangerous goods for transport purposes

Other useful links

• European Commission Joint Research Centre (ESIS)
• OECD (eChemportal)
• New Zealand (HSNO CCID)
• United States (TOXNET)

Key classification documents

• Approved Criteria for Classifying Hazardous Substances [NOHSC:1008(2004)]
• GHS (3rd revised edition)