Radiolytic gas generation after loss-of-coolant accident in a boiling-water reactor

This report elucidates the probable true supply of radiolytic gas to a nitrogen-filled pressure suppression containment under accident conditions in boiling-water reactors. Calculations have been performed using a computer-based program developed at Riso National Laboratory in Denmark. Measurements of the radiolytic gas contents in water and vapor after shutdown have been performed at Oskarshamn I. These measurements have been compared with results from computer calculations. It is concluded that, after an accident, a recombiner system would probably not be required to limit the concentration of radiolytic gas to safe values but, in any event, would only be necessary considerably later in the accident than was previously assumed