Fission Product Source Terms for the Light Water Reactor Loss-of-Coolant Accident

Models for cesium and iodine release from light water reactor (LWR) fuel rods defected in steam were formulated based on experimental fission product release data from several types of defected LWR fuel rods. The models were applied to a pressurized water reactor undergoing a loss-of-coolant accident temperature transient. Calculated total iodine and cesium releases were 0.053 and 0.025% of the total reactor inventories of these elements, respectively, with most of the release occurring at the time of rupture. These values are approximately two orders of magnitude less than those used in WASH-1400, the Reactor Safety Study.