ML20059C948
| ML20059C948 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 08/21/1993 |
| From: | AFFILIATION NOT ASSIGNED |
| To: | |
| References | |
| OLA-2-I-MFP-119, NUDOCS 9401060264 | |
| Download: ML20059C948 (13) | |
Text
!
+
do - 2 73 3 z3-Dut I-IM FP-l Ff M FY 6 p j6{T ll Y N LEAR REGULATORY COWA15SION g
Yb Docket Ni h)c2 7hd d4 Offeial Exh No.dd /f/d 6T45 a,d S LfC7All'.o %
WN g*
In tn new ct~
NCR DCl-92-TI NO39 Rev. 00 E
e:ai m ',
October 2, 1992 m
____ __ _ "inf t 50. /
p r.j g k.9 /
V in in Gu ',; t D
(-
<'
- g Canm :tsi jj
$ L p!E f' -Qd 3 0:ber u.ess R - c h il ? Fi 'n e/
v MANAGEMENT
SUMMARY
on September 6, 1992, at 1757 PDT, the Fuel Handling Building Ventilation System (FHBVS) shifted to lodine removal mode.
This event constitutes an Engineered Safety Features (ESF) actuation.
.A four-hour, non-emergency report was made to the NRC its accordance with 10 CFR 50.72 (b) (2) (ii) on September 6, 1992, at 1830 PDT.
The FHBVS shift was caused by a high radiation alarm on radiation monitor RM-55 lasting appraximately one 7econd.
The plant process computer recorded this spike on RM-59, as well as three more spikes in the following 60 seconds.
Following the event, control room operators-verified that no radiation monitors continued to alarm, and reset the-FHBVS to its normal mode of operation.
The root cause of the RM-59 high radiation alarm was determined to be personnel error.
The I&C technician that had been testing RM-58 paused to document test results as directed by the test procedure; however, upon returning to his task, he failed to recognize that he was operating the wrong channel.
The technician also failed to perform an adequate self-verification as required by I&C department policy, and therefore inadvertently actuated RM-59 instead of RM-58.
The technician had been trained and-was aware of the requirement to perform self-verification.
Corrective actions to prevent recurrence will include:
(1) counseling the technician involved to re-emphasize the importance of self-verification when concentration on a task is interrupted, (2) an I&C shop tailboard regarding this event and the importance of self-verification when i
concentration on a task is interrupted, and (3) revision of i
STP I-119A to return the FHBVS to its normal mode of operation after all testing is completed, in-order to minimize distractions during the performance of the test and mitigate the effects of any inadvertent radiation monitor-alarms.
92NCRWP\\92TINO39.PSN Page 1
of 13 1
9401060264 930821 MNC2N PDR ADOCK 05000275 G
PDR l
=
\\
NCR DC1-92-TI-NO39 Rev. 00 October 2, 1992 NCR DCl-92-TI-NO39 FHB VENTILATION SWAP - RM-59 SPIKE l
I.
Plant Conditions Plant conditions are not applicable to this-event.
II.
Description of Event A.
Event
Description:
Radiation monitors RM-58 and RM-59 are located in the Fuel Handling Building.
Radiation exceeding the radiation monitor setpoints, or radiation monitor failure, will cause the Fuel Handling Building Ventilation System (FHBVS)-.to shift to its iodine removal mode..
On September 6, 1992, between 1702 and 1754 PDT, j
Surveillance Test Procedure (STP) I-119A was being performed on radiation monitor RM-58 (ref. 3).
l This STP is a functional test that requires an I&c.
technician to:
- 1) remove power to.the radiation monitor and verify proper FHBVS operation; 2) verify that Operations. returns the FHBVS to normal, and 3) perform a source check.and test of l
the high alarm setpoint with the radiation monitor in a test mode (ref. 4).
The I&C technician had completed the first portion of the test and.
1 verified with Operations that theLFHBVS was in its normal mode, when he inadvertently. actuated 1the-high radiation alarm on RM-59 instead of RM-58.
j On September 6, 1992, at 1757-PDT, the FHBVS shifted to iodine removal mode.
This_ event' constitutes an Engineered Safety Features-(ESP) 1 actuation.
A four-hour, non-emergency report was made to the NRC in accordance with 10 CFR 50.72 (b) (2) (ii) on September;6,-1992, at 1830-PDT (ref.
I 3).
1 The FHBVS shift was causedLby a high radiation alarm.on RM-59' lasting approximately_one second I
(ref. 1).
The plant process computer recorded.
I this spike in the output signal from RM-59,--as i
well as three'more spikes in the following;60-
~l seconds.
Control room operators verified that no
[
92NCRWP\\92TINO39.PSN Page. 2 of 13 l
~
~
i
- n..
u..
a -.-
J.,
4 NCR DC1-92-TI-NO39 Rev. 00 l
October 2, 1992 radiation monitors continued to alarm, and reset the FHBVS to its normal mode of operation (ref.
l 3).
On September 6, 1992, at 1820 PDT, RM-59 was removed from service for further investigations.
l Following successful completion of functional I
testing, RM-59 was returned to service at 1846 PDT (ref. 3).
B.
Inoperable Structures, Components,.or Systems that Contributed to the Event:
None.
C.
Dates and Approximate Times for Major Occurrences:
1.
Sept.
6, 1992; 1757 PDT:
Event / Discovery date.
RM-59.high radiation alarm caused the ESF actuation.
2.
Sept.
6, 1992; 1830 PDT:
A four-hour, non-emergency report was made to the NRC in l
accordance with 10 CFR 50.72 l
(b) (2) (ii).
D.
Other Systems or Secondary Functions Affected:
None.
E.
Method of Discovery:
The event was immediately apparent to plant operators due to alarms and indications received in the control room.
l l
F.
Operator Actions:
The operators verified that no radiation monitors continued to alarm and returned the FHBVS to its normal mode of operation.
RM-53 was removed from service for further investigations (ref. 3).
92NCRWP\\92TINO39.PSN Page 3
of 13 l
l
, + ~ -
t i.
NCR DCl-92-TI-NO39 Rev. 00 October 2, 1992 G.
Safety System Responses:
The FHBVS shifted to iodine removal mode, as designed.
III.
Cause of the Event A.
Immediate Cause:
The immediate cause of the FHBVS shift was a high radiation alarm on RM-59.
B.
Determination of Cause:
Event:
ESF Actuation; FHBVS shifted to Iodine Removal Mode.
Cause:
Spurious Hi-Rad Alarm on RM-59.
Cause:
Operation of Operate Switch to Trip Adj.
on RM-59.
Cause:
Technician inadvertently manipulated RM-59 switch instead of RM-58 switch.
Operation of this switch, although it is not intended to, can result in an ESF actuation.
In this case the shift of FHBVS to Iodine Removal did' occur.
Root Cause:
Technician failed to recognize the wrong channel was being operated.
Contributory Cause: Technician did not reverify the channel being operated
.after stopping to document test data on the data sheet.
C.
Root Cause:
The root cause of the RM-59 high radiation alarm was determined to be personnel error.
The I&C technician that had been testing RM-58 paused to document test results as directed by the. test procedure; however, upon returning to his task, he failed to recognize that he was operating the wrong channel.
92NCRWP\\92TINO39.PSN Page 4
of 13
)
i d.
I NCR DC1-92-TI-NO39 Rev. 00 I
October 2, 1992 5
D.
Contributory Cause:
The I&C technician also failed to perform an adequate self-verification as required.by I&C department. policy, " Policy for Unit / Channel / Component Self-Verification," dated June 30, 1988.
The technician had been trained and'was aware of the requirement to perform self-verification.
IV.
Analysis of the Event A.
Safety Analysis:
A FHBVS shift to iodine removal mode is a conservative actuation, regardless of plant' conditions.
All FHBVS equipment functioned as designed, and would have actuated had an actual-high radiation condition existed.
Therefore, this event did not adversely affect the health and safety of the public.
B.
Reportability:
1.
Reviewed under QAP-15.B and determined to be-non-conforming in accordance with-Section 2.1.2 as an event that is reportable to the NRC.
2.
Reviewed under 10 CFR 50.72 and 10 CFR 50.73 per NUREG 1022 and determined to be reportable in accordance with 10 CFR 50~.73 (a) (2) (iv). as -
an unplanned ESF actuation..The report associated with this NCR is LER 1-92-013-00.
Submit LER 1-92-013-00 to NRC.
RESPONSIBILITY:-
P.
Natividad ECD: ~ RETURN DEPARTMENT:
Regulatory Compliance Tracking AR:
A0275711, AE #01 3.
Reviewed under 10 CFR Part'21 and determined that this problem will_not require a 10 CFR 21 report, since (a) it is being evaluated under 10 CFR 50.72/73,: and (b) it does_not involve defects in vendor-supplied services / spare i
parts in stock.
92NCRWP\\92TINO39.PSN Page 5
of 13 l
=
0 NCR DCl-92-TI-NO39 Re" 00 October 2, 1992 4.
This problem will not be reported via an INPO Nuclear Network entry.
l 5.
Reviewed under 10 CFR 50.9 and determined the event was not reportable under 10 CFR 50.9 since event was being reported under 10 CFR 50.73.
6.
Reviewed under t - critaria of AP C-29 requiring the issue and approval of an OE and l
determined that an OE is not required.
V.
Corrective Actions A.
Immediate Corrective Actions:
1.
The operators verified that no radiation monitors continued to alarm and returned the FHBVS to its normal mode of operation.
f 2.
A functional test of RM-59 was performed following the event.
No abnormal indications were noted, and all acceptance criteria were satisfied (ref. 1).
3.
The interrupted RM-58 functional test was-successfully completed on September 11, 1992.
The required testing interval was not exceeded as the RM-58 STP was not due until 9/22/92; however, the 9/11/92 test will conservatively not be credited in the recurring task schedule, so that another test will be j
scheduled prior to 9/22/92.
j B.
Investigative Actions:
1.
Document the results of investigations into the cause of the event.
RESPONSIBILITY:
D. Weatherby ECD:
RETURN DEPARTMENT:
I&C Tracking AR:
A0275711, AE #02 l
C.
Corrective Actions to Prevent Recurrence:
l 1.
Counsel the technician involved to re-emphasize the importance of self-verification when concentration on a taskLi;s interrupted.
92NCRWP\\92TINO39.PSN Page 6
of 13 l
i-I l
l.
NCR DC1-92-TI-NO39 Rev.~00 October 2, 1992-I RESPONSIBILITY:
S. Roberts ECD:- RdbURN DEPARTMENT:
I&C Tracking AR:
A0275711, AE #03 ~
Outage-Related? No-OE Related?
No NRC Commitment? Yes
[
CMD Commitment? No l
2.
Conduct an I&C shop tailboard regarding this?
event and the'importance of'self-verification when concentration on a task is1 interrupted.
1 i
I RESPONSIBILITY:
J.-Molden' ECD:
RETURN-l DEPARTMENT:
I&C Tracking AR:
A0275711,.AE #04' Outage Related? No OE Related?
No NRC Commitment? Yes CMD Commitment? No 3.
Revise STP I-119A to return the FHBVS to itsi normal-mode'of' operation after all testing is completed, in order to minimize' distractions during the performance.cuf the test and ~
f mitigate the effects of any inadvertent-radiation monitor alarms.
RESPONSIBILITY:
D. Weatherby.
' ECD:
10/16/92 DEPARTMENT:
I&C Tracking AR:
A0275711,.AE #05 Outage Related? No OE Related?
No.
NRC Commitment? Yes CMD Commitment? Yes The TRG discussed and decided not to. implement physical barriers over the switches, similar to.
those installed over'many of the other' radiation monitors'as a result of previousi" wrong-channel" personnel errors.
The.above action'to revise'STP l
I-119A will ensure that any. future RM-58/59 wrong '
channel errors will not cause. unplanned.actuations in the FHBVS,.because the system would already.be in its required iodine removal mode until all thc testing was completed.. Nevertheless, any such personnel errors would still be undesirable and-would be addressed by quality problem resolution-procedures.
1 92NCRWP\\92TINO39.PSN
'Page 7
of 13
=
NCR DC1-92-TI-NO39 Rev. 00 October 2, 1992 D.
Prudent Actions (not required for NCR closure) 1.
Prepare a HPES Case Study to provide the
" lesson learned" to the rest of the plant:
self-verification is especially important when concentration on a task is broken.
l RESPONSIBILITY:
K.
Doss Tracking AR:
A0276881 l
2.
Revise Training's generic JPM checklists to specifically emphasize the need to reperform self-verification when resuming an interrupted task.
j RESPONSIBILITY:
D.
Clifton Tracking AR:
A0279145
)
VI.
Additional Information A.
Failed Components:
None.
B.
Previous Similar Events:
i Various previous ESF actuations have_been due to personnel errors; however, none were due to j
inadvertent actuation of RM-58 or RM-59 during testing:
1.
LER 1-91-011-00, " ACTUATION OF WRONG TEST SWITCH DUE TO PERSONNEL ERROR CAUSES UNPLANNED ESF ACTUATION" The root cause of this ESF actuation was personnel error by a licensed operator.
Because the corrective actions were focused on Operations department personnel and on establishing administrative controls on the Solid State Protection System keys, the corrective actions did not prevent the current NCR/LER.
92NCRWP\\92TINO39.PSN Page 8
of 13
8 NCR DC1-92-TI-NO39 Rev. 00 October 2, 1992 2.
LER 1-91-009-00, " REACTOR TRIP DUE TO PERSONNEL ERROR AND SAFETY INJECTION DUE TO LEAKING STEAM DUMP VALVES" The root cause of this ESF actuation was personnel error by an I&C technician.
Corrective actions included physical barriers over the nuclear instrumentation drawers and additional self-verification training for the I&C department.
Because the physical barriers were on a different system and the current I&C technician failed to re-perform adequate self-verification upon returning to his task, the corrective actions did not prevent the current NCR/LER.
3.
LER 2-91-007-00, " INADVERTENT SAFETY INJECTION WHILE IN MODE 5 DUE TO PERSONNEL ERROR" The root cause of this ESF actuation was personnel error by two I&C-technicians.
Corrective actions included an I&C department tailboard and a memorandum issued by_the Vice President, Diablo Canyon Operations and Plant Manager, emphasizing the need for procedural compliance and verification.
Because the current I&C technician failed to re-perform adequate self-verification upon returning to his task, the corrective actions did not prevent the current NCR/LER.
4.
LER 1-91-005-00, " ACTUATION OF WRONG TEST SWITCH CAUSES UNPLANNED DIESEL GEN ~1ATOR START (ESF ACTUATION) DUE TO PERSONNEL ERROR" The root cause of this ESF actuation.was personnel error by a non-licensed operator.
Corrective actions included an Operations Incident Summary to re-emphasize the importance of self-verification.
Because the corrective actions were focused on Operations department personnel, the corrective actions did not prevent the current NCR/LER.
These previous corrective actions,_as well as DCPP's ongoing human performance' enhancement system (HPES) program, have'been successful in reducing the number of personnel errors since 92NCRWP\\92TINO39.PSN Page 9
of 13
l l
i l
i i
NCR DCl-92-TI-NO39 Rev. 00 October 2, 1992 l
1988.
The current rate of personnel errors this l
year to date at Diablo Canyon Power Plant is 0.27 l
per 100,000 man-hours.
PG&E recognizes that it must remain vigilant and continue to improve in reducing personnel errors.
C.
Operating Experience Review:
1.
NPRDS:
l Not applicable, s
2.
NRC Information Notices, Bulletins, Generic Letters:
Not applicable.
l 3.
Not applicable.
D.
Trend Code:
TI - A3 (Instrumentation & Controls)
(Personnel Error, Inattention to Detail).
E.
Corrective Action Tracking:
1.
The tracking action request is A0275711.
2.
Are the corrective actions outage related?
No.
F.
Footnotes and Special Comments:
l None.
t G.
References:
1.
Initiating Action Request A0275559 Action Request A0275558 2.
Licensee Event Report (LER) 1-92-013-00 3.
Control room logs dated 9/6/92 Event Notification Worksheet dated 9/6/92 E-mail from GLA1 to SS, "Dayshift Turnover, 9/6/92" dated September 6, 1992 t
92NCRWP\\92TINO39.PSN Page 10 of 13
~.
l
\\
NCR DC1-92-TI-NO39 Rev. 00 l
October 2, 1992 4.
STP I-119A, " Functional Test:
Fuel Handling
't Building Area Radiation Monitors RIS-58/RIS-59 5.
Personnel statements from I&C technicians, dated 9/6/92, 9/9/92,fand 9/14/92 6.
Annunciator typewriter and datalogger.
printouts 7.
E-mail from TDE19IC to AKJ2@QC dated September 22, 1992, "Cause Determination" H.
TRG Meeting Minutes:
On September 11, 1992, the initial TRG convened-and considered the following:
1.
The TRG discussed'the chronology of the event.
Early thoughts that the event was, caused by noise from reinstallation of the power fuse for RM-58 appear to be-incorrect - as listed
~
in the annunciator and datalogger printouts, the fusefreinstallation actually occurred several minutes prior to the event.- Other.
potential causes discussed included - 500 )d7 perturbations, RF noise (but none showed up on RM-58), and welding or:other electrical noise (but no work was being performed late.on l
Sunday when the event occurred).
l 2.
There do not seem to be any similar previous l
events (some previous' events were due to the alarm setpoints being too low); however, some I&C personnel report that spikes after this functional test is.not a new phenomenon.
This l
particular test was completed and the system i
returned to service more rapidly than before; therefore, the spike' caused the FHBVS shift,-
as designed.
3.
I&C is continuing to perform additional investigations; however, theccause of this event may remain unknown.
The.TRG discussed t
that this event is reportable, so the investigations need to be completed quickly l
and this TRG will reconvene on 9/16/92.
j 92NCRWP\\92TINO39.PSN Page 11 of 13
i l
I l
1 c.
NCR DC1-92-TI-NO39 Rev. 00 October 2, 1992-i On September 16, 1992, the TRG reconvened'and i
1 considered the following:
1.
I&C investigations have concluded that the ESF i
actuation was due to personnel: error.
The technician performing the functional test'on j
RM-58 actually performed the last part of.the i
test procedure on RM-59 inadvertently, i
2.
The TRG discussed that.the test procedure could be. improved.
. Currently, it requires that the rad monitor testing be interrupted to notify the control room to return the FHBVS to normal, before continuing testing..
The original reason for this-was to minimizeLrun time on the charcoal filters; however, the TRG discussed that the' additional time-to complete.
the testing was minimal and would not significantly affect run time.
Therefore, this step'will be moved to a section.after the-testing is completed.
This will prevent an ESF actuation during the remainder of the test.
3.
The TRG determined corrective' actions as listed in the text above.
Because the above action mitigates the consequences of a wrong-channel operation,Linstalling physical barriers similar to those installed.in' front of the NI panels would not be necessary..
4.
This TRG will' reconvene on 10/1/92 to finalize the NCR.
i On October 1, 1992, the TRG reconvened and considered the following:
1.
The root cause analysis was discussed and revised slightly.
The failure to self-verify was reclassified as a contributory cause, with the root cause being the failure to recognize the wrong channel, e
2.
The TRG revisited the discussion.on physical plexiglass barriers, as documented above in the corrective action section.
92NCRWP\\92TINO39.PSN Page 12 of-13
a..
NCR DCl-92-TI-NO39'Rev 00 October 2, 1992 3.
Training was contacted, but the TRG'was unable to definitively determine whether:JPMs'and instructors train personnel specifically'to reperform self-verification upon, interruption-of a task.
'A prudent. action was assigned to revise the generic JPM checklists to~ emphasize this. point.
4.
This TRG will not reconvene.
Final draft expected to be. signed-by 10/9/92, to PSRC 10/12/92, to QA for closure.by 10/31/92,'and overall ECD for closure is 12/30/92.
I.
Remarks:
None.
92NCRWP\\92TINO39.PSN Page 13 of 13
_