Where must the hazardous material identification number be displayed?

The hazardous material identification number is a crucial component of compliance with regulations governing the transportation of hazardous materials. It must be displayed on both the shipping papers and the packages themselves. This requirement is in place to ensure that first responders and carriers are aware of the specific type of hazardous material being transported, allowing for appropriate handling, storage, and emergency response measures.

By mandating the display of the identification number on both the shipping documents and the packages, regulations enhance the visibility of critical information throughout the shipping process. This ensures that those involved in the transportation, as well as emergency personnel in the event of an incident, can readily identify the substance involved.

The other options do not fully encompass these requirements. While including the hazardous material identification number on a company's website or invoices may be beneficial for tracking and record-keeping, it does not meet the minimum regulatory standards for safe transportation. Simply placing it on the shipping papers or the vehicle's exterior, without reflecting it on the packages, would not provide the immediate identification necessary for safe handling and response in emergencies. Thus, option B accurately captures the full regulatory requirement.