ML22070A157
| ML22070A157 | |
| Person / Time | |
|---|---|
| Issue date: | 11/12/2021 |
| From: | Chang Y, Segarra J, Jing Xing NRC/RES/DRA/HFRB |
| To: | |
| Xing, Jing - 301 415 2410 | |
| References | |
| Download: ML22070A157 (17) | |
Text
IDHEAS Suite for Human Reliability Analysis Y. James Chang, Jing Xing, Jonathan DeJesus Segarra U.S. Nuclear Regulatory Commission Presented at PSA 2021 Conference November 7 - 12
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Background===
- The Integrated Human Event Analysis System (IDHEAS) was developed under an NRC Commissions direction in 2006 to evaluate the different human reliability models to propose either a single model for the NRC to use or guidance on which model(s) should be used in specific circumstances.
- The NRC staff chose the a single model path - IDHEAS model
- Today, IDHEAS is a model with many application components (collectively, IDHEAS Suite) for performing human reliability analysis (HRA) 2
IDHEAS Suite Element Description Status IDHEAS-G General methodology - the single model Complete IDHEAS-AtPower A HEP calculation method for internal events at-power HRA applications Complete IDHEAS-ECA A HEP calculation method. Originally developed for the event and condition analysis (ECA) but was expanded for all HRA applications.
Complete IDHEAS-DATA Data basis Draft complete IDHEAS-DEP Dependency analysis Draft complete IDHEAS-TIME Estimate the uncertainty distribution of the time-required In-process IDHEAS-REC Error recovery TBD IDHEAS-ECA software tool Facilitate the implementation of IDHEAS-ECA V1.2 In progress 3
IDHEAS-G (General Methodology, NUREG-2198)
Recommended for NRC use by NRCs Advisory Committee on Reactor Safeguards Developed on the foundation of a large psychological literature review (NUREG-2114)
Include an HRA process and a toolbox to perform all process elements
- Provide technical basis, models, and guidance to perform all process elements (13 appendixes)
- An element could be modeled with different levels of detail and different approaches, e.g.,
- Failure modes: macrocognitive functions, cognitive processes, and cognitive mechanisms
- HEP quantification approaches: expert elicitation, data based, and model-based Provide equations and parameters but not the values of parameters 4
HRA Process 5
Step 1:
Develop scenario narrative Develop scenario timeline Step 1: Determine scenario context Step 1: Identify HFE Step 1: Define HFE PRA model Step 2:
Analyze tasks and identify CT(s) in HFE Step 3: Characterize the CT(s) and select applicable CFMs Step 5: Calculate Step 6: Analyze HFE timeline (subset of scenario timeline, if there are multiple HFEs in the scenario)
Step 4: Assess PIFs applicable to every CFM Step 6: Estimate parameters of distribution Step 6: Estimate parameters of distribution Step 6: Calculate Scenario context and list of applicable PIFs PIF attributes of every CFM for every CT List of CT(s)
HFE and its definition List of applicable CFM(s) for the CT(s) and and Step 7:
Calculate overall HEP
HFE and its definition HFE and its definition Step 8:
Uncertainty and dependency analysis and documentation CFM = cognitive failure mode CT = critical task HEP = human error probability HFE = human failure event PIF = performance-influencing factor PRA = probabilistic risk assessment
= error probability due to CFMs
= error probability due to uncertainty in and
= time available
= time required and = mean and standard deviation of and = mean and standard deviation of
IDHEAS HEP Quantification Model (Calculate HEP of a Human Failure Event) 6 Main Element Sub-Elements Highlights Pt (Time Insufficiency)
Convolution of the uncertainty distributions of the time-required and time-available Pc (Cognitive Errors)
Critical tasks Cognitive basis structure 5 Macrocognitive functions (Detection, Understanding, Decisionmaking, Action Execution, and Interteam) 20 PIFs, each PIF has a set of attributes Two types of PIFs (base PIFs and modifier PIFs) based on their effects on HEPs The accumulated PIFs effects on a CFM is
[probabilistic sum of the base PIFs effects] x [sum of the modifier PIFs effects] ÷ Error Recovery
IDHEAS-DATA
- Provide extensive data-basis for IDHEAS-model based HEP estimations
- Pacific Northwest National Laboratory (PNNL) is reviewing the IDHEAS-DATA draft report
- Ensure literature information is used correctly (status: PNNL completed the review)
- Determine whether the equation calculating multiple PIFs combined effects on HEP is appropriate (by 6/2022) 7
IDHEAS-TIME
- PNNL analyzes simulator data to recommend distribution for the time-required
- Data sources include EPRI, Halden HAMMLAB, KAERI, and ÚJV ez, a. s.
- Draft report available by Dec. 2021
- Only includes control room actions 8
IDHEAS-DEP (RIL-2021-14)
- Assess the dependency effects of the occurrence of HFE1 on HFE2. HFE1 occurs earlier than HFE2
- Model 3 types of dependency
- Consequential dependency, Resource-sharing dependency, and Cognitive dependency
- Include 5 relationships to assess dependency effects
- Function/system, time proximity, personnel, location, and procedure
- Three levels of analysis
- Predetermination, Screening, and Detailed
IDHEAS-DEP Predetermination Analysis (Draft Graphical User Interface) 10
IDHEAS-DEP Screening Analysis (Draft Graphical User Interface) 11
IDHEAS-DEP Screening Analysis
- Calculate the total dependency effects (Pd)
- Pd is the probabilistic sum of all applicable dependency effects
More About IDHEAS-DEP
- IDHEAS-DEP Detailed Analysis
- Requires using IDHEAS-ECA method
- The dependency effects are represented by the corresponding PIF attributes
- IDHEAS-DEP suggests the corresponding PIF Attributes for the analysts consideration
- IDHEAS-DEP status
- Report (Research Information Letter) should be available to the public in Dec. 2021 (RIL-2021-14)
- To be included in IDHEAS-ECA software tool v1.2.
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IDHEAS-ECA Software Tool (IDHEAS-ECA RIL-2020-02)
- V1.1 is available to calculate individual HEPs
- V1.2 is scheduled to be available in Jan. 2022.
- Include IDHEAS-DEP to calculate dependent HEPs
- Fixed the found issues
- Add lognormal distributions to calculate Pt 14
Calculate Pt (IDHEAS-ECA v1.1 Screenshot) 15
Calculate Pc (IDHEAS-ECA v1.1 Screenshot) 16
Conclusion
- IDHEAS advances the cognitive basis and data basis for HRA and tie to the current cognitive and behavior science literature.
- Recommended for the NRC use by NRCs Advisory Committee on Reactor Safeguards
- NRC plans to gradually replace SPAR-H with IDHEAS-ECA
- Methods and tools will be available to the public 17