Transport of radioactive goods
The class of hazard determines the specifics of the transport and security measures to be taken. The transport of radioactive material occupies a special place in logistics.
What is radioactive cargo
Radioactive cargo is materials containing hazardous substances - radionuclides. Their activity concentration exceeds permissible values. This is class 7 of the ADR international classification. Radioactive materials are subdivided into the following types:
- Corrosive; causing depressurization.
How radioactive cargo is transported
Radioactive substances are transported by air using packing systems (kits), which may consist of
- Shipments containing radioactivity must be packaged accordingly to ensure safety. The packaging includes documentation and items used. If it can be confirmed that the consignment has a low specific activity or low surface radioactive contamination, other goods can be transported together.
- The packaging is marked appropriately to warn of the special nature of the consignment.
- The carrier ensures all measures for radiation protection and the safe transport of the radioactive goods by air.
How radioactive cargo is transported
Radioactive substances are transported by air using packing systems (kits), which may consist of:
- containers (one or more);
- equipment: cooling equipment, radiation protection equipment, pressure reducing equipment
- equipment that limits the distance between the containers
- thermal insulation;
When transporting radioactive cargo by plane, a radiation power of up to 50 mbar/m is allowed
For transportation purposes, radioactive material is defined as any material which has a specific activity greater than 0.002 microcuries per gram. This definition does not specify a quantity, only a concentration.
As an example, pure cobalt-60 has a specific activity of 1,000 curies per gram, which is about 500 billion times greater than the definition. However, uranium-238 has a specific activity of only 0.3 microcuries per gram, which is only 150 times greater than the definition. Although both exceed the definition of radioactive material in their pure form, either of these materials could be uniformly mixed with enough substance, such as dirt, which would cause the concentration to fall below the definition. In the case of uranium-238, if one gram were mixed with about 150 grams of dirt (about 1/3 of a pound), the concentration could be classified as non-radioactive. Remember, however, that the definition of radioactive material above only applies for transportation
Since transport accidents cannot be prevented, the regulations are primarily designed to:
• Insure safety in routine handling situations for minimally hazardous material and
• Insure integrity under all circumstances for highly dangerous materials.
These goals are accomplished by focusing on the package and its ability to:
• Contain the material (prevent leaks),
• Prevent unusual occurrences (such as criticality), and
• Reduce external radiation to safe levels (provide shielding).
Packages Strong Tight Container
Type A Packages
Type B Packages
The three basic types of packages are strong tight containers, whose characteristics are not specified by regulation, followed by Type A containers, and finally Type B containers, both of which have very specific requirements in the regulations. A strong tight container is designed to survive normal transportation handling. In essence, if the material makes it from point X to point Y without being released, the package was a strong tight container. A Type A container, on the other hand, is designed to survive normal transportation handling and minor accidents. Type B containers must be able to survive severe accidents. Fissile materials, which could be involved in a criticality accident, also have additional requirements.
Don’t take risks with your dangerous goods, make sure they are expertly packed and adhere to all regulations.