2002 Davis-Besse Reactor Pressure Vessel Head Degradation Knowledge Management Digest (NUREG/KM-0005)

On this page:

Download complete document

Publication Information

Date Published: February 2014

Office of Nuclear Reactor Regulation
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

Availability Notice


The U.S. Nuclear Regulatory Commission (NRC) has an active knowledge management program that captures important historical events and critical information and preserves this knowledge for future generations

The 2002 reactor pressure vessel (RPV) head incident at Davis-Besse Nuclear Power Station (DBNPS) in Oak Harbor, OH, was one of the most serious nuclear safety events in United States history. In March 2002, severe degradation of the reactor pressure vessel head was discovered during a refueling outage at Davis-Besse. Boric acid had eaten away the carbon steel of the RPV head, leaving only a thin layer of stainless steel cladding to withstand the full operating pressure of the coolant in the reactor core. This could have led to a rupture of the reactor pressure vessel head and caused a major public safety event.

Eight years later, in 2010, Davis-Besse experienced another serious safety event involving the reactor pressure vessel head. During an NRC-mandated inspection, plant staff found cracking of the control rod drive mechanism (CRDM) nozzles. Had the plant staff not performed the inspection and found the cracking, the event would have progressed and could have led to a situation similar to the 2002 event.

Fortunately, in both 2002 and 2010, the problems at the Davis-Besse were discovered before they caused a major public safety event. These near-miss accidents have driven NRC policies and research to ensure the continued safe operation of the entire U.S. nuclear fleet.

This knowledge management digest and accompanying DVD contain historical documents relating to the technical and regulatory aspects of these incidents.

These documents can be accessed on the DVD through the interactive timelines or directly through the document listings.

The DVD also includes a multimedia presentation of the special NRC seminar "2002 Davis-Besse Reactor Pressure Vessel Degradation" held in January 2013, which offers a retrospective view of the 2002 incident.

Page Last Reviewed/Updated Wednesday, March 24, 2021