Which items require "Signature Service" or "Sig Serv" due to their nature?

"Signature Service" or "Sig Serv" is mandated for certain high-sensitivity items that require careful handling and accountability due to their nature and implications. Human blood and remains fall into this category because they are of critical importance, often related to medical or legal considerations. The transport of these items demands an elevated level of security and tracking, ensuring that they arrive at their destination safely and are handled in compliance with strict protocols.

In contrast, while clothing, personal items, food, and medical supplies are important, they do not necessarily carry the same level of sensitivity or require the stringent tracking and accountability measures that human blood or remains do. Thus, these items do not qualify for Signature Service under the same regulatory and safety guidelines as those that pertain specifically to biological materials.