United States Nuclear Regulatory Commission - Protecting People and the Environment

Reactor Vessel Integrity

Vessels that house reactors are bombarded with nuclear materials and must be constructed of materials that can withstand exposure to neutron irradiation and heat (the thermal environment) that occurs during fission. Licensees are required to establish surveillance programs for their reactor vessels that meet certain standards.

During years of reactor operational experience licensees have sometimes experienced problems maintaining optimum reactor vessel integrity. From this experience, NRC has accumulated information about the integrity of reactor vessels and, in 1992, developed a reactor vessel integrity database (RVID). The RVID database was subsequently updated in 2000.

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Source of the Information

NRC developed the RVID following staff review of licensee responses to Generic Letter (GL) 92-01, Revision 1, "Reactor Vessel Structural Integrity."

The database reflects the status of reactor vessel integrity for each commercial nuclear power plant in the United States as of 2000. The data are consolidated in a convenient and accessible manner. The RVID summarizes the properties of the reactor vessel beltline materials for each plant.

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Purpose

The staff uses the RVID to review information submitted by licensees.

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Access to the Data

Staff. RVID is not continuously maintained.

Public. For ease of distribution to licensees and the public, the database is provided as a Microsoft Excel TM spreadsheet via the RVID page.

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Last Update

The RVID data was last updated in July 2000. There are no current plans to update RVID.

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Related Reactor Materials Embrittlement Data

Consistent with our Open Government Plan, the NRC has issued a high-value dataset (with accompanying data dictionary) to expand the public’s knowledge about the agency’s oversight of operating reactor facilities, as it relates to embrittlement of reactor pressure vessel materials. Irradiation embrittlement is a phenomenon that occurs as a consequence of reactor operation when neutrons from the nuclear fuel irradiate the thick steel plates and welds used to construct the vessel. This irradiation embrittles the steel, making it less tough and, therefore, less capable of maintaining structural integrity in the presence of flaws that may exist following fabrication. (For additional detail, see the Fact Sheet on Reactor Pressure Vessel Issues.) The NRC obtains information on irradiation embrittlement from surveillance capsule reports obtained through the Reactor Vessel Material Surveillance Program conducted under Appendix H to Title 10, Part 50, of the Code of Federal Regulations (10 CFR Part 50). Information from these surveillance capsule reports is summarized in the RVID, along with information from other sources.

Available in open format (Microsoft Excel), this Reactor Materials Embrittlement Dataset provides access to information on surveillance capsule reports, which include reactor materials embrittlement data from the Nation’s fleet of operating nuclear power reactors. Specifically, this dataset lists each plant name and reactor type, designer, and manufacturer. It also states the plant’s license term, the date on which the operating license will expire, and whether the plant was licensed to operate as of January 1, 2011. In addition, the dataset provides the PDF filename for the plant’s surveillance capsule report, along with the report date and identification of the specific surveillance capsule. The related Data Dictionary explains each field in the dataset and provides instructions for accessing the surveillance capsule reports.

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Page Last Reviewed/Updated Tuesday, April 02, 2013