When Carbon dioxide, solid (UN 1845 dry ice) is used to keep dangerous goods cold, Carbon dioxide, solid (UN 1845 dry ice) must be placed:
- around the secondary packaging(s) and outer packaging
- in an overpack.

The primary receptacle and the secondary packaging must maintain their integrity at the temperature of Carbon dioxide, solid (UN1845 dry ice). Interior support must be provided to secure the secondary packaging(s) or packages in the original position after Carbon dioxide, solid (dry ice) has dissipated. If Carbon dioxide, solid (dry ice) is used, the outer packaging or overpack must permit the release of carbon dioxide gas. You have to mark and label the package in accordance with the Regulations of the mode of transport you used.