Paris, 3 February 1997
In a joint statement released today, the Committee on Nuclear Regulatory Activities (CNRA) and the Committee on the Safety of Nuclear Installations (CSNI) of the Nuclear Energy Agency (NEA) - the two major committees of the NEA in nuclear safety and regulation - support enhanced co-operation with the nuclear industry, and encourage the nuclear industry to take a more active role in developing the experimental and analytical basis to support its proposals for new reactor fuel designs and extended operational characteristics. The full statement of CSNI and CNRA is given below:
"Over the past several years, there has been much interest in improving the performance of nuclear fuel. Work has been performed to develop new cladding materials, new fuel designs and manufacturing processes intended to improve reliability and safety, allow higher burnup and longer fuel cycles, and support the use of MOX fuels.
Some of these new designs are currently being used in reactors and others are planned for use in the short term. However, in some cases, these new designs raise safety and regulatory issues that need to be addressed. These issues involve the fuel safety margins under accident conditions as well as the possible impact of fuel behaviour on the performance of safety systems (e.g. hindering control rod insertion). In particular, one issue relates to the cumulative effect of many "minor" changes, each of which has been deemed too small to warrant suitable research and qualification programmes. These issues were discussed by the CNRA and the CSNI at their 1996 annual meetings.
As part of their responsibilities to ensure that criteria are developed and limits are specified to assure the safety of reactor operations, some regulatory bodies and/or their technical support organisations in OECD countries are sponsoring or developing a number of fuel research programmes addressing fuel.
Behaviour under normal, transient and accident conditions, such that sufficient independent data is available to support regulation. However, ultimately the responsibility for developing an adequate safety case for introducing optimised or new fuel designs rests with the industry. Accordingly, the CNRA and the CSNI support co-operation with the nuclear industry and encourage the nuclear industry to take a more active role in developing the experimental and analytical bases to support its proposals for new fuel designs and extended operational characteristics. Issues related to cases with a mix of fuel designs should also be addressed. A more active role implies the sponsoring of adequate qualification programmes to demonstrate the performance of the fuel under normal, transient and accident conditions, the sharing of relevant information with, and the submission of well supported safety cases to regulatory bodies and their technical support organisations.
Regulatory bodies will review the adequacy of safety criteria for these new designs based upon available information, thus it is in the interest of the nuclear industry to ensure sufficient information is available to support achieving the fuel performance goals desired.