Document: NUREG-0800
Document ID: 51b93b24-7bff-4144-949f-36812854b7aa
Document Type: srp
Title: HUMAN FACTORS ENGINEERING
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1612/ML16125A114.pdf
Revision Date: 2023-06
Chapter: 18
Section ID: 18.0
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elements of the actions and performance shaping factors (e.g., workload, time pressure) that affect time required and likelihood of successful completion of the action sequence. The licensee/applicant should establish time estimates for individual task components (e.g., acknowledging an alarm, selecting a procedure, verifying that a valve is open, starting a pump) and the basis for the estimates, through a method applicable to the human-system interface (HSI) characteristics of the control system. The vendor/licensee/applicant should also provide a statement as to how elements such as diagnostics, communications, travel time, and work environment affect the time required for the action. Acceptable methods for deriving time estimates for individual task components include, but are not limited to: • Operator interviews and surveys • Operating experience reviews • Software models of human behavior, such as task network modeling • Use of control/display mockups • Expert panel elicitation2 • American National Standards Institute (ANSI)/American National Standards (ANS), ANSI/ANS 58.8, “Time Response Design Criteria for Safety-Related Operator Actions.” 3 Methods that are dependent on expert judgment to derive time estimates for task components are potentially subject to bias. In addition, the uncertainties associated with estimates derived through these methods are difficult to quantify. Accordingly, these methods should be employed using structured approaches that minimize bias and identify and assess uncertainties (see example: NUREG/CR-6372, “Recommendations for Probabilistic Seismic Hazard Analysis: 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