Globally Harmonized System (GHS)

Before GHS, countries and even industries used different definitions, symbols, and sheet formats, so the same product could be labeled differently when shipped across a border. GHS, often called the Purple Book, gives each country the same building blocks to adopt.

The system has three main parts. First, classification criteria sort hazards into hazard classes and categories. Second, labels carry six elements: product identifier, signal word, hazard statements, pictograms, precautionary statements, and supplier identification. Third, the SDS follows a fixed 16-section order.

GHS is not law by itself. Each country chooses which parts to adopt and writes its own rules. The United States aligned the OSHA Hazard Communication Standard with GHS Revision 3 in 2012 and primarily with Revision 7 in 2024, Canada did so through WHMIS 2015, and the European Union through the CLP Regulation.

Because countries may adopt only some hazard classes or categories, labels can differ slightly in different jurisdictions even though they share the same symbols and phrasing. GHS also does not replace transport rules, which have their own labels and placards.

For workers, the practical benefit is recognition: a flame pictogram or the word Danger means roughly the same thing on a product from almost anywhere.