Which label must be present on opposite sides of an overpack for a nuclear gauge?

The requirement for a radioactive label on opposite sides of an overpack for a nuclear gauge is rooted in safety regulations related to the transportation of radioactive materials. This labeling ensures that anyone handling or transporting the overpack is immediately aware of the potential hazards associated with the contents. The radioactive label is specifically designed to convey critical information about the type of materials inside, the safety precautions needed, and the necessary emergency response actions in case of an incident.

Proper labeling is crucial in ensuring not only compliance with regulatory standards but also in promoting safety among workers and emergency responders. The radioactive label provides essential warnings that help to mitigate the risks posed by exposure to radiation, thus protecting both human health and the environment. This contrasts with the other options, which pertain to different types of hazards, but do not specifically address the unique requirements of radioactive materials.