These labels are used to comply with OSHA's implementation of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS), an international consensus system developed by the United Nations for classifying and labeling hazardous chemicals. The GHS is designed to streamline the hazard assessment, labeling, and hazard communication requirements within and between the countries that adopt it by promoting common, consistent criteria for classifying chemicals according to their health, physical and environmental hazards, and to develop compatible labeling, safety data sheets (SDS's; formerly known as MSDS's) and other information based on those classifications.
OSHA incorporated many elements of the GHS into its 2012 revision of 29 CFR 1910.1200, the OSHA Hazard Communication Standard (HazCom or HCS 2012). Labels now require signal words and one or more pictograms. There are 8 GHS pictograms which incorporate 16 physical, 10 health, and 3 environmental hazards. Each label should bear no more than one instance of each pictogram, and each pictogram should be large enough to be "clearly visible."