Emergency planning zones around facilities that use radiation and nuclear technologies are set up in order to prevent or minimize deterministic effects and reduce risks of stochastic effects of radiation exposure in case of nuclear or radiological emergency. In international practice, in order to enhance effectiveness of response to emergencies, it is common to set up emergency planning zones for nuclear facilities in accordance with their level of threat for the environment and public. As the establishment of such zones requires certain material resources, the size of the zones is to be justified.
As of today, sanitary-protective zone and monitoring zone in Ukraine could be considered, to a certain extent, as analogues of such emergency planning zones. However, the main functional load of these zones are relevant more for routine operation of nuclear facilities than for the issues of emergency planning and do not have such a specific for the emergency planning zones functions as ensuring necessary infrastructure for conducting such urgent protective actions as evacuation, sheltering, notification, relocation and others in case of severe accidents at NPPs.
Absence of transparent numerical criteria for determining the size of emergency planning areas, on one hand, and necessity to determine such areas as required by the key IAEA publication GSR Part 7, as well as due to understanding the importance of emergency planning areas in the state emergency response system, on the other hand, make the task on establishing approaches to the definition of the scope of emergency release, which is a framework for emergency zoning, crucial.
The paper proposes to discuss two approaches to defining the scope of the boundary release, according to which the size of the emergency planning areas is to be defined. The paper presents results of assessing the size of the emergency planning areas around NPPs based on the scope and radionuclide composition of the boundary release.
2. Radiation Safety Standards of Ukraine NRBU-97. State Health and Safety Regulations. DGN 6.6.1-6.5.001-98. Approved by Resolution of the Chief State Medical Doctor of Ukraine No. 62 dated 01 December 1997.
3. Homann, S., Aluzzi, F. HotSpot 3.0 Software Manual, LLNL-SM-636474.
4. NP 306.2.141-2008. General Safety Rules for Nuclear Power Plants. Approved by SNRIU Order No. 162 dated 19 November 2007 (registered in the Ministry of Justice of Ukraine under No. 56/14747 dated 25 January 2008).
5. INTERNETIONAL RTM-95. Volume 2. U.S. Regulatory Commission.
6. Collection of maps of Chornobyl exclusion zone. (1996). Radioenvironmental Centre of the National Academy of Sciences of Ukraine.
7. NP 306.2.173-2011. Requirements for determining the size and boundaries of the NPP observation area.