March 25, 1996
Dear Mr. Leventhal,
Thank you for your letter of 26 February 1996 concerning the transport of radioactive material by aircraft which has been circulated, as you requested, to the Members of the TRANSAC during their last meeting in Vienna.
The Agency, in conjunction with Member States' safety regulatory authorities, has considered many transport safety issues to determine where enhancements in the requirements are prudent. These enhancements have been extensively considered over the past several years and include more stringent requirements for the transport of substantial quantities of radioactive material by aircraft. My technical staff assure me that new, significantly more rigorous requirements will be imposed for the transport of such materials.
The more stringent requirements include rigorous technical specifications to ensure that the transported materials are either of very low dispersibility and limited radiation hazard (LDM) or, that they be packaged in more accident resistant (Type C) packagings if the materials are dispersible. The technical specifications for demonstrating low dispersible material ensure that the material transported, when subjected to the same mechanical and thermal tests as a Type C package, produce only inconsequential dispersion. That is, the material itself, with no credit for its packaging, must meet these performance criteria. Only then can such materlals be packaged in the currently required Type B category of package, which has consistently demonstrated an ability to survive severe accidents.
The requirements for low dispersible radioactive material which have been developed and included in the draft regulations are the performance and acceptance criteria that are believed to provide the necessary degree of non-dispersibility. It still remains to be determined whether mixed oxide fuels you mentioned in your letter can meet these stringent requirements.
To the best of our knowledge, no test regimes and protocols have been completely developed by potential package designers to demonstrate how material can be tested to the very stringent performance and acceptance requirements. It is not possible to know which matenals, if any, will qualify as LDM until the materials have been tested and the results accepted by the competent authorities of all countries involved in their shipment.
Strengthening the international transport safety standards requires developing consensus on the need for improvements and the degree to which they are justified. Let me assure you that the Agency and the safety regulatory agencies representing the Member States in our revision process are giving this matter very careful consideration.
Deputy Director General
Head of the Department of Nuclear Safety