ASTM E1018-26

1.1 This guide covers the establishment and use of an ASTM-recommended file that consists of a set of nuclear data cross sections, uncertainty data, and associated product decay data for analysis of single or multiple sensor measurements in neutron fields related to light water reactor (LWR) pressure vessel surveillance (PVS). These fields include in- and ex-vessel surveillance positions in operating power reactors, benchmark fields, reactor test regions, and research reactors.

1.2 Requirements for establishment of ASTM-recommended cross section files address data format, evaluation requirements, validation in benchmark fields, evaluation of error estimates (covariance file), and documentation. A further requirement for components of the ASTM-recommended cross section file is their internal consistency when combined with sensor measurements and used to determine a neutron spectrum through such approaches as a least squares spectrum adjustment.

1.3 Specifications for use include: identification of the energy region of applicability, data processing requirements, and application of uncertainties.

1.4 This guide is directly related to and should be used primarily in conjunction with Guides E482 and E944, and with Practices E185 and E693.

1.5 The ASTM-recommended file for cross sections, uncertainty data, and associated product decay data represents a generally available data set for use in sensor set analysis. However, the availability of this data set does not preclude the use of other validated nuclear data, either proprietary or nonproprietary. When alternate cross section files that deviate from the requirements laid out in this standard are used, the deviations should be noted to the customer of the dosimetry application.

1.6 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.

1.7 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.