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ASME OM Code Meeting Notes - December 2003

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Prepared By: Ron Lippy

Company: True North Consulting

Meeting Dates: December 2 - 5, 2003

Meeting Location: St. Petersburg Beach, Florida

Meeting Notes

General Requirements (ISTA)


·        ROM-03-06—Editorials/changes to ISTA completed and submitted for Balloting to MC.

·        V-03-06a—Definition of Repair/Replacement related to pump and valves—Closed, no change to existing Code.

·        V-03-07—Proposed ISTE requirements for SOVs to include/exclude wording to verify design bases of SOVs.—Determined to be excluded from OM Code.

·        Discussion on “pre-conditioning” on whether to address in the Code (again).—Stay tuned.


IST Valves (ISTC)


·        V-02-01—Rapid Acting valve criteria for SOVs/AOVs to be evaluated as to the possibility of either increasing the 2 second limit or somehow modifying the Code requirements to allow a “relaxed” rapid acting valve acceptance criteria.—Determined by the Sub-group to “leave-as-is”.  No Code changes to be initiated at this time.  Sufficient guidance exists.  Most of the concerns identified by the industry were of the following:

o       Valve was determined to be in a “degraded” or “degrading” condition.

o       Valve reference values were incorrectly evaluated regarding rapid acting valve criteria.

o       Valves were incorrectly incorporated as “rapid acting valves”.

·        MOVs (OM-8)

o       Discussion on OMN-1 Code Case, Rev.1 to be out for balloting to Main Committee ~March 2004.  Significant technical changes have occurred including scoping and methodology of testing as well as frequency of exercising, for certain MOVs.

o       Significant comments on ISTE regarding adequacy of methodology for testing certain LSSC MOVs in the risk informed arena.

o       Code Case OMN-1 inquiry:

“Is it the intent of ASME Code Case OMN-1, paragraph 3.6.1, to verify that each motor operated valve assembly tested under the scope of ISTA has been exercised on a frequency not to exceed once every 18 months for a plant with an 18 month fuel cycle or, 24 months for a plant with a 24 month fuel cycle, instead of during a refueling cycle?”

Proposed Reply:  No

Action:  This is being treated as an “intent inquiry” and a change is being made to OMN-1 Code Case stating that the intent for exercising the MOV under the Code Case is a “period of time” (i.e. 12 months, 18 months, or 24 months,), rather than an “event” related frequency of required exercising.

·        AOVs (OM-19)

o       Code Case for AOVs (OMN-12), is being turned into a Mandatory Appendix.

§         Scope Increase

Ø      Mitigate consequences of a transient

Ø      Causes Reactor Trip or Turbine rollback

Ø      Important to plant operation

Ø      Maintain Integrity of RCPB

Ø      In addition to the typical IST scope requirements

§         Once Appendix is invoked for an AOV, ALL remaining AOVs/HOVs must eventually be incorporated into the Appendix.

·        Safety and Relief Valves (Appendix I)

o       Change definition of “ambient temperature” to “temperature range”.

o       Change definition of “normal system operating conditions” to include “temperature range”.

·        Check Valves (OM-22)

o       Working on possible Code change to allow D&I during operations rather than refueling outages.

o       Revisions to Appendix II to allow previous history info to be used to establish CV condition and, to not require “full stroke exercise” open of CV.


Pumps (ISTB)


·        P03-02—Evaluate definition of “pump design flow”.  Redefined the “pump design flow” to state that “a flow rate which is at a relatively high flow point on the pump curve where relatively small changes in the flow rate results in a relatively large change in differential pressure.”

·        P03-03—Evaluate allowing the performance of a Group A pump test Quarterly (meeting the definition of “pump design flow”, as stated in P03-02 above), in lieu of a Comprehensive Pump Test.  Concerns exist to the differences between the Group A and the CPT (i.e., pressure instrumentation tolerance, acceptance criteria and reference point).

·        P03-05—Reformat of ISTB for usability by separating the Inservice testing requirements from the preservice testing requirements.

·        ROM 01-20 withdrawn—This change was to allow the re-establishment of pump operability by the allowance of mini-recirc testing.  Several new ROMs were created to address the various pump issues that were to be addressed under ROM 01-20, (non-instrumented mini-recirc tests, PMT, CPT and Group A reference point establishment, acceptance criteria for CPT and Group A, definition of “pump design flow”, reformatting of ISTB).

·        ROM 01-21 (Ballot 03-087)—Changes made to ISTB-1200 to clarify the “flexible coupling” as an exclusion.  1 negative to essentially define the “rigid coupling” rather than the “flexible coupling”.  SCOMC is sending ballot for 2nd consideration with no changes.


Snubbers/Supports (ISTD)


·        Code Cases for extension of exam frequency and test frequency are being submitted for approval


Diesel Generators


·        New proposal to develop a standard or Appendix for testing DGs is progressing


Risk Informed (ISTE)


·        ROM 00-09—Incorporate RIIST into OM Code dropped.  Entirely new ROM being submitted.  Significant changes being made addressing comments regarding testing methods and frequency as well as acceptance criteria for HSSC and LSSC components.

·        Change in ISTE Project Management

·        Major concerns associated with ISTE which need to be addressed

o       Scoping

o       Test Methods

o       Test Frequency

o       Appears to be at too high of a level with little or no guidance as to how to meet requirements associated with LSSC and HSSC components.




·        New standard is being developed to provide LSSC testing guidance for RI-IST programs for the RISC-3 category (LSSC).




·        Draft rule for 50.69—Comments received and being evaluated/incorporated.  Due to be issued ~6/04.

·        Draft final rule for 50.55a endorsing up to the 2003 addenda of Section III, XI, and the OM Code to be issued for comment ~1/04.  Should issue Final Rule for 50.55a ~9/04.

·        RI-ISI method for addressing weld exams/components for BER (Break Exclusions Regions), the EPRI method has been approved and the WOG method should be approved soon.

·        NUREG 1482 revision working.  Due to complete end of 2004???

·        New revision to RG 1.147, 1.192 and 1.193 should be drafted and out for public comment ~2/04.  Will address/endorse OMN Code Cases thru OMN-13.

·        Generic Communications issued since last meeting affecting IST

o       IEB 2003-01, Potential Impact of Debris Blockage on Emergency Sump Recirculation at PWRs

o       GL 2003-01, Control Room Habitability

o       IN 2003-17, Reduced Service Life of ASCO solenoid valves with Buna-n material.

·        Symposium July 12-14, 2004 in Washington DC.  OM Code meeting to follow.

OM Code meeting July 14-16, 2004 in Washington DC following P&V Symposium. Next OM Code meeting 12/04 at St. Petersburg, Florida (Same as 2003).

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