Information Notice 1986-50, Inadequate Testing to Detect Failures of Safety-Related Pneumatic Components or Systems

Inadequate Testing to Detect Failures of Safety-Related Pneumatic Components or Systems

ML031220684
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Skagit, Marble Hill
Issue date:	06/18/1986
From:	Jordan E NRC/IE
To:
References
IN-86-050, NUDOCS 8606160044
Download: ML031220684 (4)

ORIGINAL SSINS No.: 6835 IN 86-50 UNITED STATES.NUCLEAR REGULATORY

COMMISSION

OFFICE OF INSPECTION

AND ENFORCEMENT

WASHINGTON,,D.C.

20555 June 18, 1986 IE INFORMATION

NOTICE NO. 86-50: INADEQUATE

TESTING TO-DETECT

FAILURES OF SAFETY-RELATED

PNEUMATIC

COMPONENTS

OR SYSTEMS

Addressees

All nuclear power reactor facilities

holding an operating

license (OL) or a construction

permit (CP).

Purpose

This notice is being provided to alert recipients

to a potentially

significant

problem pertaining

to inadequate

testing practice relating to air operated valves. The NRC expects that recipients

will review this notice for applica-bility to their facilities.

However, suggestions

contained

in this notice do not constitute

NRC requirements;

therefore, no specific action or written response is required.Past Related Correspondence:

IE Information

Notice No. 82-25, "Failures

of Hiller Actuators

Upon Gradual Loss of Air Pressure," July 20, 1982 IE Information

Notice No. 85-35,- '.Failure

of Air Check Valves to Seat," April 30, 1985 IE Information

Notice No. 85-84, "Inadequate

Inservice

Testing of Main Steam Isolation

Valves," October 30, 1985 IE Information

Notice No. 85-94, 'Potential

for Loss of Minimum Flow Paths Leading to ECCS Pump Damage During a LOCA," December 13, 1985 Description

of Circumstances:

The NRC has reported previously

on instances

where safety-related

equipment failed to operate as intended when non-safety-related

pneumatic

systems were unavailable (IE INs 82-25 and 85-35). In these situations, main steam isola-tion valves and containment

isolation

valves failed to operate properly when control air pressure decreased

slowly rather than rapidly as would be expected for an air line break. In the case of IN 85-35, the fault was exposed by a loss of offsite power test, and in the case of IN 82-25, the fault was exposed by a preoperational

test designed .to simulate a slow air leak. In both cases, 8606160044 IN 86-50 June 18, 1986 the components

in question--an

accumulator

isolation

check valve (IN 85-35) and pneumatic

selector valves (IN 82-25)--were

not tested adequately.

Several recent events have indicated

continuing

problems of similar nature. These events are discussed

below.On February 13, 1986, the licensee at Turkey Point Unit 3 first reported to tht NRC a concern that the component

cooling water (CCW) system might fail to meet its functional

requirements

for a design-basis

accident.

One part of the concern involved the CCW heat exchanger

outlet control valve. This valve regulates

flow of intake cooling water (ICW) to this heat exchanger.

Loss of control air, coincident

with a loss of offsite power, a valid engineered

safeguards

features (ESF) actuation

signal, and a loss of an emergency

diesel generator (EDG) would cause this valve to fail closed. If this happened, the CCW heat exchanger

would not receive sufficient

flow of ICW. This situation was discovered

during a design review of the ICW system. Earlier disclosure

might have been possible if ICW operation

had been considered

or tested with non-safety-related

control air secured, coincident

with loss of electrical

power.On January 7, 1986, the licensee at Robinson Unit 2 reported a concern with the air-operated

valves in the safety injection (SI) pump minimum-flow

recircula- tion line from the pump discharge

to the refueling

water storage tank (RWST).This concern evolved from review of IN 85-94. Two such valves had been insert-ed in series in this line and had been designed to fail closed on loss of non-safety-related

air or loss of electrical

power to the valves. The purpose of the valves is to protect the RWST (outside containment)

from highly radioac-tive reactor coolant during the long-term

circulation

phase of accident recov-ery. In the event of SI initiation

under small-break

loss-of-coolant-accident

conditions

concurrent

with closure of either of these valves, the SI pumps would be operating

with no flow until reactor pressure decreased

below their shutoff head. This would damage the SI pumps after only a short time. The licensee's

remedy was to put mechanical

blocks on the air operators

so the valves would fail as-is (open). Again, if SI operation

had been considered

or tested with non-safety-related

control air secured, the fault might have been disclosed

earlier.On December 9, 1985, the licensee at Catawba Unit 2 reported finding that one of the two valve closure springs was missing on one of the pressurizer

power-operated

relief valves (PORVs). Thus, with loss of air the valve would not have closed against system pressure.

The other two PORVs had their normal complement

of springs. The valve with the missing spring had been found satisfactory

in preoperational

tests. During the preoperational

loss of air test, the valve closed because system pressure was not present; during the hot functional

test, the valve closed because actuator air pressure was present.This is clearly a case in which a fail safe valve was tested without all actuator power secured (IN 85-84).

IN 86-50 June 18, 1986 No specific action or written response is required by this information

notice.If you have any questions

about this matter, please contact the Regional Administrator

of the appropriate

regional office or this office.;d~waA tJordan, Director Divisi of Emergency

Preparedness

and E gineering

Response-~ Office of Inspection

and Enforcement

Technical

Contact: Vern Hodge, IE (301) 492-7275 Attachment:

List of Recently Issued IE Information

Notices

Attachment

1 IN 86-50 June 18, 1986 LIST OF RECENTLY ISSUED IE INFORMATION

NOTICES Information

Date of Notice No. Subject Issue Issued to 86-49 86-48 86-47 Age/Environment

Induced Electrical

Cable Failues Inadequate

Testing Of Boron Solution Concentration

In The Standby Liquid Control System Feedwater

Transient

With Partial Failure Of The Reactor Scram System Improper Cleaning And Decon-tamination

Of Respiratory

Protection

Equipment Potential

Falsification

Of Test Reports On Flanges Manufactured

By Golden Gate Forge And Flange, Inc.6/16/86 6/13/86 6/9/86 6/12/86 6/10/86 86-46 86-45 86-44 All power reactor facilities

holding an OL or CP All BWR facilities

holding an OL or CP All BWRs and PWRs facilities

holding an OL or CP All power reactor facilities

holding an OL or CP and fuel fabrication

facilities

All power reactor facilities

holding an OL or CP and research and test facilities

All power reactor facilities

holding an OL or CP and research and test reactors All power reactor facilities

holding an OL or CP All power rector facilities

holding an OL or CP All byproduct material licensees Failure To Follow Procedures

6/10/86 When Working In High Radiation Areas 86-43 Problems With Silver Zeolite Sampling Of Airborne Radio-iodine 86-42 Improper Maintenance

Radiation

Monitoring

Of Systems 6/10/86 6/9/86 6/9/86 86-41 Evaluation

Of Questionable

Exposure Readings Of Licensee Personnel

Dosimeters

OL = Operating

License CP = Construction

Permit