Document: NUREG-0800
Document ID: eedf1a7c-578e-463a-9608-b06af6312cf1
Document Type: srp
Title: HUMAN FACTORS ENGINEERING
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1310/ML13108A095.pdf
Revision Date: 2023-06
Chapter: 18
Section ID: 18.0
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ted actions and the actions identified in the operating experience. 2 For an example of an expert panel elicitation, see NUREG-1852, “Demonstrating the Feasibility and Reliability of Operator Manual Actions in Response to Fire.” 3 ANSI/ANS 58.8, “Time Response Design Criteria for Safety-Related Operator Actions,” provides an acceptable task decomposition methodology for this purpose. However, the time intervals described in ANSI/ANS 58.8 were validated using analog controls and; therefore, may not be accurate for this application. 18.0-19 Draft Revision 3 – July 2015 A time margin should exist between the analyzed time(s) as the difference between time available and time required for operator action is a measure of the safety margin and as it decreases, uncertainty in the estimate of the difference between these times should be appropriately considered. This uncertainty could reduce the level of assurance and potentially invalidate a conclusion that operators can perform the action reliably within the time available. One acceptable method is for the time margin to equal the maximum recovery time for any single credible4 operator error. The basis for the specific time margin used in the analysis should be justified and documented. Insights from the HFE program, especially the operating event report (OER) and human reliability analysis, should be used. The identification of potential errors, error detection methods, and error recovery paths in event trees may be used to provide estimates of how much margin should be added to the operator response time estimates. For complex situations and for actions with limited margin, such as less than 30 minutes between time available and time required, a more focused staff review will be performed. 1.B. Review Criteria The responsible reviewers evaluate licensee/applicant’s submittals for compliance with the following criteria: • An analysis establishes the time available. The basis for the time available is