A Material Safety Data Sheet (MSDS) provides essential health and safety information about hazardous substances, including their properties, safe handling procedures, and emergency response instructions, and suppliers are legally required to provide a current MSDS for any hazardous substances they supply to workplaces. An MSDS describes a hazardous substance's identity, physical and chemical properties, health hazards, precautions for use, and safe handling procedures. Employers must obtain and make available a current MSDS for any hazardous substances present in the workplace.