Fission product release mechanisms during reactor accident conditions

During postulated accidents the reactor fuel is estimated to be exposed to a variety of conditions. These conditions are dynamic and, during the cours e of an accident, the fuel may experience a wide range of temperatures and conditions from highly oxidizing to mildly reducing environments. The expos ure of the reactor fuel to these environments and temperatures may affect i ts stoichiometry and release performance. In this paper a review of the imp ortant fission product release mechanisms is presented. The results of thre e out-of-pile experimental programs are also summarized. (C) 1999 Elsevier Science B.V. All rights reserved.