Standard Practice for Determining Neutron Exposures for Nuclear Reactor Vessel Support Structures
|Publication Date:||1 June 2018|
|ICS Code (Nuclear power plants. Safety):||27.120.20|
This practice covers procedures for monitoring the neutron radiation exposures experienced by ferritic materials in nuclear reactor vessel support structures located in the vicinity of the active core. This practice includes guidelines for:
Selecting appropriate dosimetric sensor sets and their proper installation in reactor cavities.
Making appropriate neutronics calculations to predict neutron radiation exposures.
The values stated in SI units are to be regarded as standard; units that are not SI can be found in Terminology E170 and are to be regarded as standard. Any values in parentheses are for information only.
This practice is applicable to all pressurized water reactors whose vessel supports will experience a lifetime neutron fluence (E > 1 MeV) that exceeds 1 × 1017 neutrons/ cm2 or exceeds 3.0 × 10−4 dpa.(1)2 (See Terminology E170.)
Exposure of vessel support structures by gamma radiation is not included in the scope of this practice, but see the brief discussion of this issue in 3.2.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. (For example (2)) 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2 The boldface numbers in parentheses refer to a list of references at the end of this practice