ML18005A193

LER 87-052-01:on 870831,mechanic & Health Physics Technician Exiting Containment Through Personnel Access Hatch When One of Door o-ring Seals Fell Out of Groove.Caused by Personnel Error.Work Request Issued to Repair door.W/871102 Ltr

ML18005A193
Person / Time
Site:	Harris
Issue date:	11/02/1987
From:	Schwabenbauer, Watson R CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
HO-870531-(O), LER-87-052, LER-87-52, NUDOCS 8711050107
Download: ML18005A193 (10)

Text

REGULA ( INFORMATION DISTRIBUTI YSTEM (RIDS)

ACCESSION NBR: 8711050107 DOC. DATE: 87/11/02 NQT*R IZED: NO DOCKET I FACIL: 50-Roa Shearon Harris Nuclear Poeer Planti Unit 1i Carolina 05000400 AUTH. NAME AUTHOR AFF ILI AT I QN SCHWABENBAUER CaT olina Power <<Light Co.

WATSQNi R. A. Carolina Power 5 Light Co.

REC IP. NAME REC IP I ENT AFF I L I*7 ION

SUBJECT:

LER 87-052-01: on 870831i mechanic 5 health physics technician exiting containment through personnel access hatch when one of door o-ring seals fell out of groove. Caused bg personnel error. Worl< request issued to repair door. W/871102 ltr.

DISTRISUTION CODE: IE22D COPIES RECEIVED: LTR l ENCL J SIZE:

TITLE: 50. 73 Licensee Event Report (LER)> Incident Rpti etc.

NOTES: Application for permit reneeal filed. 05000400 REC IP lENT COP IES REC IP IENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-1 L* PD2-1 PD BUCKLEY'S B 1 1 INTERNAL: ACRS MICHELSQN 1 ACRS MOELLER 2 2 AEOD/DOA 1 AEOD/DSP/NAS 1 AEOD/DSP/RO*B 2 2 AEOD/DSP/TPAB 1 ARM/DCTS/DAB 1 DEDRQ NRR/DEST/ADS 0 NRR/DEST/CEB 1 NRR/DEBT/ELB 1 NRR/DEST/ ICSB 1 NRR/DEBT/MEB 1 1 NRR/DEST/MTB 1 NRR/DEST/PSB 1 1 NRR/DEBT/RSB 1" NRR/DEST/SQB 1 1 NRR/DLPG/HFB 1 1 NRR/DLPG/GAB 1 1 NRR/DOEA/E*B 1 NRR/DREP/RAB 1 1 NRR/DREP/RPB 2 2 NR D /SIB 1 .1 NRR/PMAS/ ILRB 1 1 F E 02 1 1 RES DEPY GI 1 1 RDi J 1 RES/DE/EI 8 1 1 RGN2 FILE 01 1 1 EXTERNAL: EGScQ GROHi M 5 5 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC HARRISi J 1 1 NSIC MAYS> G 1 1 TOT*L NUMBER QF COPIES REQUIRED: LTTR 45 ENCL 44

NRC Form 358 UA. NUCLEAR REOULATORY COMMISSION (94)3) APPROVED OMB NO. 31500104 EXPIRES: 8/31/88 LICENSEE EVENT REPORT (LER)

PACE 3 FACILITY NAME (ll DOCKET NUMBER (2) 0 5 0 0 0 g PP 1OF 08 CONTAINMENT INTEGRITY BREACH CAUSED BY PERSONNEL OPENING INNER PERSONNEL ACCESS DOOR WHILE OUT LARED N PERABLE DUE TO 0-RING SEAL I

D EVENT DATE (5) LER NUMBER (8) REPORT DATE (7) OTHER FACILITIES INVOLVED (SI MONTH OAY YEAR YEAR r': SEOVENTrAL NVMSER .~r NUMBER MONTH OAY YEAR FACILITYNAMES DOCKET NUMBERISI 0 5 0 0 0 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT 'TO THE REOUIREMENTS OF 10 cFR ()r /Cnec/r one or more o/ th ~ /or/or//np/ (11)

OPERATINQ MODE (9) 20.402(ir ) 20A05(e) 50.73(el(2) (Ir) 73.71(lr)

POWER 20.405(el(1) (il 50DS(e) (I ) 50.73(e I (2) (r) 73.71(el LEVEL (10) 20.405(e) (I l(ll 50.35(c) (2) 50.73(e)(2)(rill OTHER /Spec//y /n Atrrrrect

//crow enr//n Text, NRC Form 20.405(e I (1)(BI) 50.73(e)(2) II) 50.73(e) (2) (riiil (Al 36BA/

20.405 (e) () ) (Ir) 50,73(e l(2) (8 I 50.73(el(2) (riiil(SI 20.405(el(1 l(rl 50.73(e)(2 I (IIII 50,73(e)(2) (x)

LICENSEE CONTACT FOR THIS LER (12I NAME TELEPHONE NUMBER AREA CODE R. Schwabenbauer Regulatory Compliance Technician 91 93 62- 266 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

'

MANUFAC. REPORTABLE MANUFAC EPORTABLE.

CAUSE SYSTEM COMPONENT CAUSE SYSTEM COMPONENT TURER TURER TO NPRDS TO NPRDS 9g; v Ycr P ~ ~, r P

A( re SUPPLEMENTAL REPORT EXPECTED (14) MONTH OAY YEAR EXPECTED SU 8 MISSION DATE (IEI YES /1/ yer, comp/ere EXPECTED SUBMISSION DATE/ NO ABSTRACT /L/m/t to 1400 rpecn, / A, eppmx/metely ///teen 1/np/eepece rypewrrtren //nn/ (18)

The plant was in Mode 3, Hot Standby, at 0 percent reactor power on August 31, 1987.

A mechanic and a Health Physics (HP) technician were exiting containment through the personnel access hatch. As they opened the outer door, one of the door's o-ring seals fell out of its groove. A mechanic noticed there was no apparent damage to the o-ring so he re-installed it prior to closing the door. Meanwhile, a HP technician on duty at the door notified the Shift Foreman of the situation, who immediately declared the Personnel Access Hatch inoperable and made an announcement over the site PA system for any personnel in containment who need to exit to use the Emergency Access Hatch while repairs were being made to the door. Shortly thereafter, another mechanic and HP technician, who were inside containment opened the inner door to exit containment while the outer door was still declared inoperable, the inner door was opened one minute. This violated containment integrity and Technical for'pproximately Specifications 3.6.1.3 Action a.

The immediate corrective action was a work request was issued to repair the door. The o-ring was inspected and found to be in satisfactory condition,and reinstalled. A local leak rate was then successfully completed at 1309 hours and the airlock declared operable.

The cause of the event has been determined 'to be personnel error due to a communication breakdown, as the personnel in containment stated they heard an announcement but could not understand it and were unaware the access hatch was declared inoperable.

Actions to prevent recurrence are the containment PA system and procedures are being reviewed for possible improvements. Also, a door operator is being stationed at the door to ensure proper operation of the door and adequate communication exists.

8711050107 871102 PDR ADGCI/', 05000400 NRC Form 358

US. NUCLEAR REOULATORY COMMISSION N@ FONII 3BEA LICENSEE EQJT REPORT (LERI TEXT CONTINUA'N APPAOI/EO OMB NO. 3150M(04 EXPIAESI 8/31/88 FACIUTY NAME (1) DOCKET NUMBER (2) LER NUMBER (8) PACE (3)

YEAR SEOUENTIAI. REVISION Shearon Harris Nuclear Power Plant NUMBER NUMBER Unit 1 TEXT ///mBm <<rot /B /BEN/md, uw BI/////CAB/NRC FomI 3664's/ ((7) 0 5 0 0 04ppS 0 5 2 01 02 O'0 8 DESCRIPTION:

The plant was in Mode 3, Hot Standby, at 0 percent reactor power on August 31, 1987.

A mechanic and a Health Physics (HP) technician were exiting the containment building through the Personnel Access Hatch (EIIS:BD). The inner door was shut and the door signal initiated. Just as the outer door opened, a loud 'pop'as heard

'open'uter and there was the audible sound of escaping air. The o-ring seal was observed to fall out of the retaining grooves as the door opened. The air flow was observed to be from the seal pressurization cavity and continued for one to two minutes until a nearby operator secured air flow by shutting valve 1PP"352 (refer to Figures 1, 2, 3, and 4). The mechanics pushed the seal back into the groove, closed the door, and re-opened valve 1PP-352. There was no indication of any seal leakage. In a normal operating sequence, the open signal shuts valve 1PP-353 to isolate the air supply'nd opens 1PP-355 to vent any trapped air. Operating experience has demonstrated that the door locking ring will not rotate to the unlocked position when the seal is pressurized. Valve 1PP"353 either failed to operate or failed to shut fully. When the door opening sequence was repeated, the failure of valve 1PP-353 could not be repeated and no further work was done on it.

Meanwhile, a HP technician on duty at the door notified the operations shift foreman of the situation with the access door o-ring. The shift foreman immediately declared the Personnel Access Hatch inoperable and made an announcement via the site PA system, (EIIS:FI) that any personnel in containment to exit through the Emergency Access Hatch if they needed to exit prior to repairs being completed to the airlock door.

Shortly thereafter, another mechanic and HP technician, who were in containment, opened the Personnel Access Hatch inner door while the outer door was still declared inoperable, the inner door was open for approximately one minute which violated containment integrity and Technical Specification 3.6.1.3 Action a.

The mechanic and HP technician stated they had heard an announcement over the PA system but could not understand it and were unaware the Personnel Access Hatch had been declared inoperable.

A work request was immediately issued to repair the door seal. The door seal o-rings were inspected and found to be in satisfactory condition and reinstalled on the door. A local leak rate test was successfully completed at 1309 hours0.0152 days <br />0.364 hours <br />0.00216 weeks <br />4.980745e-4 months <br /> in accordance with Engineering Surveillance Test (EST)-219, Personnel Air Lock Door Seals Local Leak Rate Test, and the Personnel Access Hatch declared operable.

NRC FORM SBBA *U.S.GPO:1988 0.62B 538/455 I+43 I

NIIC Form 36(IA U.S. NUCLEAR REGULATORY COMMISSION (983 l LICENSEE E T REPORT (LER) TEXT CONTINUA N APPROVEO OMB NO. 3150M(04 EXPIRES: 8/31/88 FACILITYNAME (1l COCKET NUMBER (21 LER NUMBER (61 PAGE (3)

SEQUENTIAL REVISION yEAR,gg phj

.rK Shearon Harris Nuclear Power Plant NUMSSR NUMSSR Unit 1 0 5 0 0 0 4 p 87 0 52 0 1 P 3 QF 0 8 TEXT //I'mrve <<>>Ce /8 mrFrkvr/, v48 afChdor>>/HRC form 3884'4/ (ITI GAUSE:

The root cause of the event was the o-ring seal on the access hatch door falling out of its groove which led to the Personnel Access Hatch being declared inoperable. This failure in conjunction with the inability to communicate the inoperable status of the outer door led to a violation of Technical Specifications 3.6.1.3 Action a. The cause of the seal failure and communication failure are discussed below.

The o-ring seal could be unseated from it's groove by 1) adhering to the door face, 2) air pressure behind the seal forcing the seal out, or 3) a fit such that the o-ring is not properly retained in the groove. The second item has been determined to be the cause of the o-ring coming unseated. The space between the seals is normally pressurized whenever the door is in the locked position or when preparations are being made to test the door. Air from the penetration pressurization system is valved in on door cl.osure and vented off at the beginning of the door opening sequence.

If valve 1PP-353 fails to close completely or valve 1PP-355 fails to open completely air will be trapped behind the seal and the pressure will force the o-ring out of its groove. A failure of the pressurization and vent valves could not be reproduced at SHNPP. However, CPGL has learned that another identical installation has experienced this problem. This occurs even when the air pressure is low enough to allow the locking ring to rotate.

Technical Specification 3.6 ' ' Action a was violated because -of the inability to effectively communicate with personnel in containment. At the time of the event the plant was near normal operating temperature and pressure. Under these conditions, the containment is hot and noisy and personnel inside of containment, which were contacted, stated that PA announcements are not intelligible inside the containment building.

ANALYSIS:

This event is being reported in accordance with 10CFR50.73 (a)(2)(i)(B) as a breach of containment integrity and a violation of Technical Specifications 3.6.1.3 Action a.

In this case only the outer door was declared inoperable and use of the inner door is prohibited pending repairs and testing of the outer door.

It has been concluded by the facts (1) the outer door seal o-ring was inspected and found to be in satisfactory condition, and (2) successful completion of local leak rate test, EST"219, that the leakage of the airlock during a postulated accident would have been acceptable.

NRC FORM 388A *U.S.GPO:198841 624 538/455

NRC Form 304A US. NUCLEAR REGULATORY COMMISSION (94)31 LICENSEE EIT REPORT (LERI TEXT CQNTINUAGIN APPROVED OMB NO. 3150-0104 EXPIRES: 8/31/ES FACILITYNAME (1) DOCKET NUMBER (2) LER NUMBER (8) PAGE (3)

YEAR SEGUENTIAL rUi62 REVISION NUMBER 4rO NUMSER Shearon Harris Nuclear Power Plant :re:r Unit 1 o s o o o 4 008 7 0 5 2 0 1 04 oF 08 TEXT //F moro rpwo lr otu/red, uro //I/rmr/SAC %%dnn 3/)849/ (IT)

ANALYSIS: (continued)

The worst case would occur during accident conditions where a breach in containment integrity could- result in radioactive activity releases in excess of allowable limits. The failure to maintain the operable door shut exposes the plant to the possibility of an accident where the inoperable door will be the barrier relied upon. This exposure is very short. The inner door was open for only a minute and the inner door could not be opened unless the outer door is fully locked shut. The closure of the outer door even with indeterminate seal leakage still presents a significant barrier to the release of radioactive material from containment.

Refer to LER-87-034-00 for a similar event where personnel entered and exited containment when one airlock door was declared inoperable due to damaged o"rings.

CORRECTIVE ACTION:

The immediate corrective action was to repair the outer door seal o-ring and to declare the outer door operable.

ACTIONS TO PREVENT RECURRENCE

1) The design and installation of Containment PA system is being reviewed for possible improvement.

2) Alternative communication methods are being investigated.

3) Procedures are being reviewed to see if corrections're required.

4) A door operator is now being posted at the airlock door to ensure ,whenever entries are made into containment that proper operation of door and adequate communication exist when a door is declared inoperable NRC FORM SESA *U.S.GPO:1988.0 824 538/458 IAIDO'I'I

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Carolina Power 8 Light Company HARRIS NUCLEAR PROJECT P.O. Box 165 New Hill, NC 27562 NOV 0 2 198?

File Number: SHF/10-13510C Letter Number'H0-870531 (0)

UPS. Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF"63 LICENSEE EVENT REPORT 87-052"01 Gentlemen.

In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. The original report fulfilled the requirement for a written report within thirty (30) days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September, 1983.

Revision 1 is being submitted as a result of an investigation into the cause of the o-ring coming unseated.

Very truly yours, R. A. Watson Vice President Harris Nuclear Project RAW'skm Enclosure cc.'Dr. J. Nelson Grace (NRC RII)

Mr. B. Buckley (NRR)

Mr. G. Maxwell (NRC SHNPP)

/~e MEM/LER-87-052/Page 1/OS1