A comparison of transient dose model predictions and experimental measurements

The RADTRAN and RISKIND transportation risk analysis computer codes are the primary tools used to estimate dose consequences and risks associated with the transport of radioactive material. Over the years, some of the mathematical models used within the two computer codes have been updated and the methodologies to calculate input parameters have been improved. In addition, both codes have been evaluated for ease of use and appropriateness of application and verified against other computer codes that perform similar calculations. However, neither code has been validated against experimental data. This report discusses the results of five sets of experimental measurements used to partially validate the specific mathematical models used to predict the dose to an individual due to a passing shipment of radioactive material within the RADTRAN and RISKIND computer codes. Based on the comparisons it was found that RISKIND most closely predicted the measured dose in the majority of the investigated scenarios and that 12 out of 14 cases demonstrate the expected inverse relationship between the measured dose and the distance of closest approach. Only half of the data demonstrated the expected inverse relationship between dose and speed of travel.