ABSTRACT
R adiation-generated radioactive sources (R) or from fissile materials (N) constitutes a hazard to the health of anyone exposed. The exposed persons can be members of the
public, patients undergoing therapy or diagnostic procedures, or workers occupied within practices involving these materials. However, if used as planned, these sources will pose a relatively moderate hazard to exposed individuals compared with situations when the radiation source is not under control or if intentionally used for malevolent acts. Therefore emergency preparedness against radiological and nuclear incidents is of key concern for the general crisis management. A first step in building up an emergency preparedness against RN events is to identify and assess the various threats and scenarios leading to uncontrolled radiation exposures. The next step is to design remedial actions to obtain control of the exposure situations, to mitigate continued exposure and to remediate the exposure and harm already endured. The remedial actions, however, come with a price; not only by means of economic costs to the society but also in terms of the harm inferred to the affected individuals. Therefore actions taken must be subject to similar radiation protection principles as for practices done under controlled situations. Although experts and decision makers from a wide range of disciplines and specialties are involved in the crisis management of RN events, the radiation protection expert has the central role in that they are basically the only ones who can quantitatively assess the radiological situation by means of radiometry. Various methods of detecting the presence of enhanced radiation must be developed. All parties involved must then be regularly trained on these methods including the radiation protection experts themselves. The most important feature in the radiological assessment by the expert is the interpretation of the detector readings into tangible risks to the affected individuals and the other actors involved in the emergency management. A large variety of situations in which such interpretations must be done can be expected in an RN event, from the local damage site up to the expert panel directly advising the director generals of the affected authorities.
