What is the primary responsibility for determining and classifying the hazards of chemicals under HCS?

The primary responsibility for determining and classifying the hazards of chemicals under the Hazard Communication Standard (HCS) falls to the producers and importers of the chemicals. This is because they have access to the necessary data regarding the chemical's composition and the potential hazards it may pose. They conduct the required evaluations, following specific guidelines, to classify hazardous chemicals appropriately.

By classifying these hazards accurately, producers and importers play a crucial role in ensuring that proper labels and safety data sheets (SDS) are provided. This information is vital for the safe handling, storage, and use of chemicals in workplaces, allowing employers and employees to understand and mitigate risks associated with chemical exposure. While employers and employees also have roles in communicating and handling hazards, the initial responsibility for hazard classification is specified to be with the producers and importers.