Pressurized Water Reactor Control Rod Ejection and Boiling Water Reactor Control Rod Drop Accidents

The U.S. Nuclear Regulatory Commission (NRC) is issuing for public comment draft regulatory guide (DG) DG-1327, ``Pressurized Water Reactor Control Rod Ejection and Boiling Water Reactor Control Rod Drop Accidents.'' This DG proposes new guidance for analyzing accidents such as control rod ejection for pressurized water reactors and control rod drop for boiling-water reactors. It defines fuel cladding failure thresholds for ductile failure, brittle failure, and pellet-clad mechanical interaction and provides radionuclide release fractions for use in assessing radiological consequences. It also describes analytical limits and guidance for demonstrating compliance with regulations governing reactivity limits.