METHODOLOGIES FOR ASSESSING THE RADIOLOGICAL IMP ACT ARISING FROM THE TRANSPORT OF RADIOACTIVE MATERIALS

The paper seeks to provide advice on the suitability of existing radiological consequence models for specific transport situations. The review was commissioned by the Health and Safety Executive of the United Kingdom as part of its programme of research to provide a firm basis for its requirements in relation to transport operations. Many mathematical models were identified as having been applied to transport issues. Four important models were selected for closer scrutiny: CRAC 2, RADTRAN II, INTERTRAN and MARC. Large deterministic codes, for example CRAC 2 and MARC, are useful when applied to situations that warrant detailed probabilistic assessments of radiological consequences. This may be the case for large notional releases from Type B packages, which may be shown to be of particular significance from the results of a less detailed consequence model, for example, in a risk analysis code, such as RADTRAN II or INTERTRAN. It is noted that all attempts to quantify the risk from the transport of radioactive materials suffer from a lack of good input data concerning the probabilities of occurrence for defined accident severity categories and the associated values for release and aerosolization factors.