Computer-based tools for radiological assessment of emergencies at nuclear facilities in the United Kingdom

HMNll is responsible for regulating the activities at licensed nuclear sites in the UK. In the event of an emergency being declared at any of these sites. HMNll would mobilize an emergency response team. This team would, interalia, monitor the activities of the operator at the affected site, assess the actual or potential radiological consequences of the event and provide briefings to senior members of government. Central to this response to an emergency is the assessment effort that would be provided by the Bootle Headquarters Emergency Room. To facilitate the assessments carried out at Bottle, computer based tools have been developed. The major licensed nuclear facilities in the UK fall into two broad groups, civil power reactors and nuclear chemical plant. These two types of facilities pose different levels of radiological hazard as a result of their different radioactive inventories and the different physical processes in operation. Furthermore these two groups of facilities pose different problems in assessing the radiological hazard in emergency situations. This paper describes the differences in approach used in designing and using computer based tools to assess the radiological consequences of emergencies at power reactor and chemical plant sites