Radiation Risk Reduction - A Graded and Pragmatic Operational Approach Adapting the UK NPP Philosophy to Help Control Radiation Risk in Planned Exposure Situations

In the United Kingdom (UK) the Nuclear Power Plants (NPP) use a graded approach to designating radiation areas to facilitate control of access which is commensurate with the risk. The UK philosophy is summarised and the method adapted to produce a generic approach to radiation control. It is hoped this simplified approach will help inform and guide applications and situations where the depth of experience of NPP is not available to assist the development of radiological safety culture Current UK radiation protection legislation is based on the Euratom BSSD, and UK Health and Safety legislation puts the onus on the owner of the risk to reduce that risk to a level which is As Low As Reasonably Practicable (ALARP). The use of ALARP, rather than As Low As Reasonably Achievable (ALARA), comes from 'Reasonably Practicable' having been tested in the UK law courts, noting this was prior to the first UK NPP being built. The radiation employer must also restrict or control access to areas where radiation exposure could exceed certain levels, namely 1 mSv/y and 6 mSv/y whole body dose. The approach to how UK NPP design and operation meets these requirements is the focus of the first part of the presentation. The starting point is to translate the annual dose limits to dose rates, as this is what is measured in operation and used in the design phase. The UK sub-divides the controlled area into further zones to give an indication of the increasing radiation hazard, as shown.