Transport of Radioactive Material
The framework
The IAEA transport regulations underpin national rules. Know the package types: excepted, industrial (IP-1, IP-2, IP-3), Type A, Type B(U) and Type B(M), and Type C. Type A is for limited activity; Type B for higher activity; Type C for air transport of high-activity material. Know the required tests: Type A minor (normal conditions); Type B and C include accident conditions (drop, puncture, fire, immersion).
Consignments
Know the transport categories (I-WHITE, II-YELLOW, III-YELLOW) based on dose rate at the package surface and at 1 m, and the transport index for exclusive-use and non-exclusive-use shipments. Placarding, segregation, driver training and emergency information are required.
Traps
- Confusing surface dose rate limits with transport index limits.
- Assuming a Type A package can carry any activity - special form and non-special form limits differ.
- Forgetting that low specific activity and surface-contaminated objects have specific provisions.
- Mixing up exclusive use (higher dose rates permitted with controls) with general consignments.
Rule of thumb
If the question mentions accident conditions, the answer is Type B or Type C, not Type A.
Worked example
A package has a surface dose rate of 0.8 mSv/h and a transport index of 4. It falls in category III-YELLOW (surface dose rate above 0.5 mSv/h up to 2 mSv/h, transport index above 1 up to 10).