ML23206A159
| ML23206A159 | |
| Person / Time | |
|---|---|
| Issue date: | 07/27/2023 |
| From: | Sushil Birla NRC/RES/DE |
| To: | |
| Sushil Birla 301-415-2311 | |
| References | |
| Download: ML23206A159 (6) | |
Text
Identifying Hazards from Engineering Digital I&C Systems:
State of the Art Presenter: Sushil Birla Office of Nuclear Regulatory Research Division of Engineering The views expressed herein are those of the author and do not represent an official position of the U.S. NRC.
1 July 27, 2023 Halden (HTO) Workshop:
Modern Hazard Analysis for Safety Assurance
Objective Assess through discussion:
1.
Can the state-of-the-art techniques identify all significant hazards in the design of a cyber-physical system as simple as a nuclear reactor protection system?
2.
If not:
1.
Limitations?
2.
Promising directions to overcome these limitations?
2
Insignificant: Support consistent judgment Safety claim satisfied unconditionally Residual uncertainty has insignificant effect.
No one can find:
- Any uncontrolled hazard.
- Any unmitigated defeater.
The safety claim is not satisfied with the given evidence.
The evidence gaps are identified.
The safety claim does not hold.
- Fallacies in logic.
- Deficiencies in evidence.
Judge 3
State-of-the-art: Meaning State-of-the-art State-of-the-practice Current practice Capability demonstrated in leading-edge implementations.
Not yet scaled up.
Best-in-class; best practices, e.g.:
as seen in leading-edge industry consensus standards Prolific in many organizations 4
Reference Framework Plans Concept Requirements Architecture Detailed design Implementation Testing Verification Validation (V&V)
Vp System Development HAp Requirements from NPP Safety Analysis HAc HAr HAr HAdd HAi HAi Vc Vr Va Vdd Vi Vt Safety Engineering Adapted from IEEE Std 1012 5
Acronyms HAp - Hazard analysis of plans HAr - Hazard analysis of requirements HAa - Hazard analysis of architecture HAdd - Hazard analysis of detailed design HAi - Hazard analysis of implementation HAt - Hazard analysis of testing (including test specifications and oracles)
IEEE - Institute of Electrical and Electronics Engineers NPP - Nuclear Power Plant NRC - U.S. Nuclear Regulatory Commission V&V - Verification and Validation Vp - V&V of plans Vr - V&V of requirements Va - V&V of architecture Vdd - V&V of detailed design Vi - V&V of implementation Vt - V&V of testing (including test specifications and oracles) 6