ML20126J721
| ML20126J721 | |
| Person / Time | |
|---|---|
| Issue date: | 12/17/1992 |
| From: | Correia R Office of Nuclear Reactor Regulation |
| To: | Zech G Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 9301060275 | |
| Download: ML20126J721 (4) | |
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DEC 171992 MEMORANDUM FOR: Gary G. Zech, Chief Performance and Quality Evaluation Branch Division of Licensee Performance and Quality Evaluation FROM: Richard P. Corraia, NRC Coordinator for NRC/NUMARC Maintenance Interactions Performance ad Quality Evaluation Branch Division of Licensee Performance and Quality Evaluation
SUBJECT:
MEETING
SUMMARY
-- DECEMBER 3-4, 1992 NRC/NUMARC PUBLIC MEETING ON THE-STATUS OF THE VERIFICATION AND VALIDATION OF THE INDUSTRY GUIDELINE FOR THE IMPLEMENTATION OF THE MAINTENANCE RULE (10 CFR 50.65)
The subject meeting was held at the NRC Headquarters Offices. The list of attendees is provided as enclosure 1. ,
The purpose of the meeting was to discuss the results to date of the '
NUMARC/ industry effort to verify and validate the industry guideline to implement the requirements of the Maintenance Rule (10 CFR 50.65). During. the meeting, NUMARC representatives presented the preliminary results from the verification and validation (V&V) process which could effect the contents of the NUMARC guideline, 93-01, revision 2A (dated July 1992). In summary, the items discussed were as follows:
- The two risk significance determination methods and the accompanying narrative regarding the use of PRA as a tool _ to determine risk significant 1 structures, systems and components (SSC) should be embellished.to: add one new method, clarify the two existing methods, and highlight that utilities that choose this PRA based approach should use all three methods.
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- SSC failure rates or unavailability due to failures should be included in performance criteria by which SSC performance will be monitored-and evaluated.
- The guideline should be changed to clarify the use of the word
" hypothetical" as it relates to SSC failures that cause reactor scrams-or actuations of a safety-related system.
- The guideline implementation logic diagram (figure-1) should be modified to include a step which requires the establishment of performance criteria for i non-risk significant stand-by SSCs.
- Additional guidance should be included to state that utilities must l demonstrate preventative maintenance effectiveness for SSCs placed under provision (a)(2) of the rule. %/J g'
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- The guideline should clarify to what extent SSCs that are under the direct control of the utility should be considered for inclusion under the scope of the maintenance rule. The NRC working group proposed that any SSCs that are located on the owner controlled area, regardless of what organization the utility may have established to maintain them, should be considered for inclusion within the scope of the mainteiance rule. For example, the equipment that feeds the offsite electrical power t.ircuits and that connects the two physically independent offsite electrical power circuits to the onsite electrical distribution system (required by 10 CFR 50, Appendix A, GDC 17) should be considered for inclusion within the rope of the maintenance rule.
= The guideline should be clarified to state at what frequency, repetitive maintenance preventable functional failures of non-risk significant, normally operating SSCs should be evaluated for goal setting and monitoring under-the govisions of (c)(1) of the maintenance rule. Guidance should be provided for utilities to aggregate SSC failures of plant level performance criteria over a reasonable time period after corrective actions have been determined and implemented to perform evaluations of failures for inclusion under (a)(1) of the rule.
. More examples should be provided in the guidelines for SSCs used in E0Ps that would not fall under the scope of the rule because they would be used for equipment protection and not accident mitigation reasons.
Additionally, the NRC and NUMARC representatives discussed some of the more significant items the participating utilities have identified during the V&V program.
. Similar NSSS plants will not necessarily have similar SSCs or sir,ilarly designated SSCs that fall under the scope of the rule. Utility and AE design preferences / requirements are the main reason for these differences.
- Plant specific PRA insights will most likely be used by utility expert panels to datermine risk significant SSCs.
- Benefits can be realized by evaluating maintenance effectiveness at the system / train lesel rather than at component level. Actual system / train performance should be compared to those assumed in the plant PRA.
Equipment failure cause determinations should be improved because some past evaluations of maintenance problems were incomplete.
Existing plant data systems generally do not adequately support utility needs for the impleaentation of the rule. Generally, much of the data is collected but is not integrated into a single data base to evaluated maintenance effectiveness.
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' Gary G.' Zech
- The method currently used to' assess overall plant safety prior to taking_
equipment out-of-service for preventative maintenance may need refinement at some facilities. Currently, some utilities rely on licensed operator experience and technical specifications as a-basis .for taking equipment out-of-service for maintenance. ,
Orfgnalsigned by:
Richard P. Correia, NRC Coordinator-for NRC/NUMARC Interactions cc: J.Sniezek ;
W. Russell -
C.Heltemes !
R.Baer l DISTRIBUTION:,._, JKopeck (0PA)(2G5) KConnaughton (16 H3) .i (Central;filei;f Rebecca_Nease (16 G15) WMinners (NLS007)_
s PDRJar EMMckenna (16 H3) GMizuno.(15 B18)
RPEB'R.F. CERossi MRing (RIII)
NRC Mtg. Participants RZimmerman ASerkiz (NLS 314)
NUMARC Mtg. Participants TFoley STreby (15'B18)
DTrimble (16113) CPetrone WTravers (11'H21);
-EDoolittle (16 H3) CAder (NLS 324) SReynolds (11 H21)-
.JScarborough'(16H3) PBaranowsky (9112) 0FC SC:RPEB:DRIL g1AMEL RCodr'[fatct DATEL * */ r. /92 / -/92 / -/92 / 1/92' /- '/92-0FFICIAL RECORD COPY.
Document Name: NUMARC27.VV k
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Enclature 1-1 Attendance' List-NRC/NUMARC Public Meeting on the Maintenance Rule Guideline Verification and-Validation December'3-4, 1992:-
Name Organization Telephone R. Correia NRC/NRR (301) 504-1009 T. Stetka NRC/ Region.1V (817) 860-8247/
- 0. Rothberg NRC/RES (301) 492-3924-
'(301) 492-3548 C. Johnson NRC/RES P..O'Reilly NRC/AE00 '(301) 492-8858 W. Smith NUMARC ~(202) 872-1280' D.. Rains NUMARC .(202) 872 1280-J. Eaton NUMARC. .(202).872-1280 G. Grant NRC/EDO' -(301)=504-1726:
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