Abstract
A dose assessment program, called RADAPAS (Rapid Dose Assessment Program from Activated Sodium in Criticality Accidents), was developed to evaluate absorbed dose to an exposed person from induced activity of sodium-24, 24Na, in human body. A generally used personnel computer is available to run the developed program. RADAPAS prepares databases of energy spectra and dose conversion coefficients, which had been derived beforehand from Monte Carlo calculations with the MCNP-code. Information necessary for dose calculation is given by a dialogue method with interface displays. The dose to human body can be estimated from measured specific activity of 24Na using the incorporated data and the interactively specified condition in RADAPAS. In order to validate its availability, RADAPAS was implemented to assess radiation dose in an experiment carried out at the Transient Experiment Critical Facility (TRACY) and for heavily exposed persons in the first criticality accident in Japan. The results show that RADAPAS is applicable to estimation of the magnitude of absorbed dose to a victim to determine initial medical treatment soon after a criticality accident.
