IEEE IEC 63260-2020 pdf free.Guide for incorporating human reliability analysis into probabilistic risk assessments for nuclear power generating stations and other nuclear facilities.
This guide provides a structured framework for the incorporation of human reliability analysis (HRA) into probabilistic risk assessments (PRAs).
1.2 Purpose
The purpose of this guide is to enhance the analysis of human-system interactions in PRAs, to help ensure reproducible conclusions, and to standardize the documentation of such assessments. To do this, a specific HRA framework is developed from standard practices to serve as a benchmark to assess alternative ways of incorporating [IRA into PRA.
2. Definitions, acronyms, and abbreviations
2.1 Definitions
For the purposes of this document, the tbllowing terms and definitions apply. The IEEE Standards Dictionary
Online should be consulted for terms not defined in this clause.5
NOTE—Several terms used in this guide and in the field of HRA are important, yet are ambiguous in common usage or not used frequently enough to be well known. They are defined in this clause for the use in understanding and following this guidc.
basic cent: An element of the probabilistic risk assessment model for which no funher decomposition is performed because it is at the limit of resolution consistent with available data.
3.1.1 Importance of human reliability
In assessing the risk associated with a nuclear power plant, the analyst should consider not only the reliability of plant hardware systems hut also the reliability of people’s interactions with other plant or Support personnel and with the plant’s equipment and systems. The scope of interactions with plant equipment and systems should include those in the control room and at local control stations and with both manually controlled and automated systems.
3.1.2 Importance of integrated HRA and PRA
An I IRA should be an integral part of a PRA. In PRAs, the quality of the analysis (e.g., quantification of human error) is dependent upon the analyst’s ability to identify scenarios and the expected human actions. This guide provides a specific approach that, if applied, will standardize the integration of HRA into the PRA process. The breakdown and order of the steps presented arc not so important; all of the steps and their activities, however, should be found within any IIRA. This approach is well established for design-basis PRAs. The approach applies to beyond design-basis analyses such as those used for severe accidents. However, as the uncertainty and variability of the plant state and accident scenario evolution increase, so too does the complexity of performing the analysis. The steps outlined in this guide should be considered at a minimum; additional steps may be appropriate for certain cases, such as severe accident analyses.
3.2 Overall evaluation issues
The focus of this guide is restricted to the incorporation of the HRA integrally into a PRA. This includes the tbllowing issues:
a) The compatibility of an HRA with the PRA of which it is a part;
b) The relationship between the way in which an HRA is performed. its philosophy, and the results or insights that may be obtained;
c) Matching the best suited HRA method to the analysis requirements; and
d) The limits of an IIRA or its results.
3.2.1 PRA compatibility
The HRA process proposed is suitable to all levels of a PRA given defined human failure events. If these are not defined, then this guidance cannot be applied successfully. The risk focus of a PRA requires the quantitative results of an HRA to be probabilistic in nature. Applications of PRAs to risk management efforts require that the BRA documents in sufficient detail the analyst’s human factors considerations for the human failure events. The PRA can have a diverse range of applications, the objectives of which may not be completely identified prior to the assessment. The [IRA process should be flexible enough to anticipate some of the likely applications of the results of the IIRA. For example, this may include design changes. procedure changes. training development, safety evaluations, or technical specification modification.IEEE IEC 63260 pdf download.