What type of container is used to ship radioactive materials by air?

In the context of shipping radioactive materials by air, the correct choice is Type C containers. Type C containers are specifically designed to safely transport large quantities of radioactive materials, particularly those that have high levels of radioactivity. They are built to withstand the rigorous conditions of air transport, including significant impacts and temperature variations, while maintaining the integrity of the material inside.

Type C containers comply with stringent regulations set forth by international and national governing bodies, ensuring that any potential hazards posed by the radioactive materials are minimized during transit. These containers are equipped with advanced safety features, such as multiple layers of shielding and secure closures, which prevent the release of radioactive materials even in the event of an accident.

While other types of containers, like Type A and industrial containers, may be used for shipping different categories of hazardous materials, they do not meet the stringent requirements set for high-radioactivity shipments needed for air transport. Excluded containers typically pertain to materials that fall below regulatory thresholds, meaning they do not contain sufficient levels of radioactivity to require special handling measures. Thus, they would not apply to the transport of radioactive materials that necessitate the robust design and specifications of Type C containers.