Infectious substances must be assigned:

Infectious substances, which are categorized under hazardous materials, are assigned a UN Identification number as well as a category for proper identification and handling. The UN Identification number is vital as it provides a unique reference to recognize the specific hazardous material; it is crucial in ensuring safe transportation and handling. The accompanying category indicates the level of hazard associated with the substance, ensuring that handlers and emergency responders can take the appropriate precautions.

Having both elements fulfills regulatory requirements and enhances safety protocols, making it clear how the substance should be treated throughout its life cycle, from transport to disposal. This dual requirement is designed to ensure that individuals working with or near these materials have by-their-side clear guidelines about the nature and risks of the infectious substance they are dealing with.