Patent Number: 
Section: claims

1. A packaging device for the transport and/or storage of a radioactive medium generating flammable gases and/or explosives via radiolysis, the said device comprising at least one canister intended to contain the radioactive medium, the said canister defining an inner storage space accessible via an opening for filling of the medium, on which plug-forming means are mounted,characterized in that:the said device also comprises a structure forming a chamber, and where said canister is arranged outside of said structure forming the chamber, and said canister is removably mounted on an exterior of said structure,and means for placing in communication allowing a first fluid communication to be set up between the said inner storage space and the said chamber. 2. The packaging device according to claim 1, characterized in that:the canister further comprises a first orifice opening into the inner storage space,in that the said chamber-forming structure comprises a second orifice opening into the said chamber,and in that the said first and second orifices form the two opposite ends of the said first fluid communication. 3. The packaging device according to claim 2, characterized in that the said means for placing in communication comprise a first member mobile between an open position in which it sets up the said first fluid communication, and a second closed position in which it shuts the said second orifice, the said first mobile member being mounted on the said chamber-forming structure. 4. The packaging device according to claim 2, characterized in that:the canister further comprises a third opening into the inner storage space,in that the said chamber-forming structure comprises a fourth orifice opening into the said chamber,and in that the said means for placing in communication allow a second fluid communication to be set up between the said inner storage space and the said chamber, the said third and fourth orifices forming the two opposite ends of the said second fluid communication. 5. The packaging device according to claim 2, characterized in that:the canister further comprises a third orifice opening into the inner storage space,in that the said chamber-forming structure comprises a fourth orifice opening into the said chamber,in that the said means for placing in communication allow a second fluid communication to be set up between the said inner storage space and the said chamber, the said third and fourth orifices forming the two opposite ends of the said second fluid communication,and in that a fifth and a sixth orifice are provided in the chamber-forming structure, and communicate with each other via a connecting duct forming an integral part of the said means for placing in communication. 6. The packaging device according to claim 5, characterized in that the said means for placing in communication comprise a first mobile member and a second mobile member each mounted on the said structure forming a chamber and able to be moved between an open position and a closed position, the said first mobile member being designed so that:in open position, firstly it places in communication the said first orifice with the said fifth orifice, and secondly it sets up the said second fluid communication by placing in communication the said third orifice with the said fourth orifice;in closed position, firstly it ensures the placing in communication of the fourth orifice with the said fifth orifice, and secondly it prohibits the communication of each of the fourth and fifth orifices with the outside of the said chamber,and in that the said second mobile member is designed so that:in open position, firstly it places in communication the said sixth orifice with the outside of the said chamber, and secondly it places the said second orifice in communication with the outside of the said chamber;in closed position, firstly it ensures the placing in communication of the sixth orifice with the said second orifice, and secondly it prohibits the communication of each of the second and sixth orifices with the outside of the said chamber. 7. The packaging device according to claim 3, characterized in that the said canister comprises an additional first mobile member, mobile between an open position in which it sets up the said first fluid communication, and a closed position in which it shuts the said first orifice, either one of the first mobile member and additional first mobile member being a leading member and the other a follower member of the actuating member, so that the movement of the actuating member from its closed position to its open position leads the said follower member also to move from its closed position to its open position, and conversely. 8. The packaging device according to claim 7, characterized in that the said actuating member also forms a mechanical connection member for the said canister on the chamber-forming structure. 9. The packaging device according to claim 8, characterized in that the said actuating member is designed so that its movement from its closed position to its open position, with the said canister bearing upon the first mobile member, ensures a mechanical connection of the canister, and so that the movement from its open position to its closed position ensures mechanical disconnection of this canister. 10. The packaging device according to claim 9, characterized in that the said actuating member forms a male or female part of a bayonet mechanical connection. 11. The packaging device according to claim 1, characterized in that it comprises a plurality of canisters each associated with means for placing in communication allowing a first fluid communication to be set up between its inner space and the said chamber. 12. The packaging device according to claim 11, wherein the means for placing in communication of all the canisters share the same second orifice,and a second mobile member is designed so that:in open position, firstly it places in communication each of sixth orifices with the outside of the said chamber, and secondly it places the said single second orifice in communication with the outside of the said chamber;in closed position, firstly it ensures the placing in communication of each of the sixth orifices with the said single second orifice, and secondly it prohibits the communication of the single second orifice and of each of the sixth orifices with the outside of the said chamber. 13. An assembly comprising the said packaging device according to claim 1, each canister housing in its inner storage space a given volume of radioactive medium, defining a level forming a horizontal boundary line with a gaseous headspace completing this inner storage space, the said means for placing in communication associated with the said canister having a first orifice opening into the said inner storage space, and arranged so that at all times it is in communication with the gaseous headspace, irrespective of the spatial orientation of the said canister integrating the said given volume of medium. 14. The assembly according to claim 13, characterized in that the said first orifice is provided at least in part in a duct projecting inside the said inner storage space. 15. The assembly according to claim 14, characterized in that the said first orifice opens in the vicinity of a baric centre of the said inner storage space. 16. A package for the transport and/or storage of a radioactive medium, characterized in that it comprises an overpack forming a cavity inside which an assembly according to claim 13. 17. Container for the transport and/or storage of a radioactive medium, characterized in that it comprises an overpack forming a cavity inside which a packaging device according to claim 1 is housed. 18. A method for packaging a radioactive medium in a device according to claim 1, wherein:the radioactive medium is introduced into the inner storage space of the canister;the canister is sealed using plug-forming means; andthe said first fluid communication is set up between the said inner storage space and the said chamber.