What is a unique requirement for packaging dry ice?

The requirement that the packaging for dry ice must allow for the release of gas during sublimation is crucial due to the nature of dry ice, which is the solid form of carbon dioxide. As dry ice sublimates, it transforms directly from a solid into gas, and this process generates pressure within a closed container. If the packaging does not allow gas to escape, it can lead to an increase in pressure that can cause the container to burst, posing safety risks.

Ensuring that the packaging is designed to release gas helps to maintain safe conditions during transport and storage, as it prevents the buildup of pressure. This unique requirement reflects the specific hazards associated with dry ice and highlights the importance of proper packaging standards in the transportation of dangerous goods. Using suitable materials that permit gas release while still being robust enough to contain the dry ice is essential for safe handling and compliance with regulations.