Final answer:
Containers of hazardous chemicals must be labeled with a product identifier, signal word, hazard statement, and precautionary measures, but not the manufacturer's phone number when leaving the workplace.
Step-by-step explanation:
When containers of hazardous chemicals are leaving the workplace, they must be labeled with specific information to ensure proper handling and safety. However, not all information is required for the label. According to the OSHA and the United States Department of Transportation regulations, a container must be marked with the product identifier, signal word, hazard statement, and precautionary measures. The one piece of information that is not required on the label when a hazardous chemical leaves the workplace is the c) Manufacturer's phone number.