ML20086D659

Proposed Tech Spec 3/4.4.3 Re Operability of PORV & Block Valves & Safety & Relief Valves

ML20086D659
Person / Time
Site:	Sequoyah
Issue date:	11/21/1991
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20086D658	List: ML20086D655 ML20086D659
References
NUDOCS 9111260210
Download: ML20086D659 (14)

Text

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I ENCLOSURE 1 j IROPOSED TECilNICAL SPECIFICATION CHANGE I

SEQUOYAH' NUCLEAR PLANT UNITS 1'AND 2

~ DOCKEf NOS, 50-327 AND 50-328 (TVA-SQN-TS-91-13)

LIST OF AFFECTED PAGES Unit 1 3/4 4-4a B 3/4 4-2

, Unit 2 ll 3/4 4-B B 3/4 4-2 l

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9111260210'911121

-PDR fiDOCK - 03000327 P Pl>R -

REACTOR COOLANT SYSTEM RELIEF VALVES - OPERATING LIMITING CONDITION FOR OPERATION -

3.4.3.2 Two power relief valves (PORVs) and their associated block valves shall be OPERABLE.

APPLICABILITY: MODES 1, 2, and 3. R16 ACTION:

a. With one or more PORV(s) inoperable, but capable of RCS pressure control, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> either restore the PORV(s) to OPERABLE status

- or close the associated block valve (s); otherwise, be in at least HOT STANDBY foll owing within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in -GGb4 SHUTOOWN within the hours. hot

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b. ,

With one PORV inoperable and incapable of RCS pressure cor.cci, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> either restore the PORY to OPERA 8LE status or close the associated block valve and remove power from the block valve; restore the PORV to OPERABLE status within the f,llowing 72 hrurs er be in HOT within the STANDBY following within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and ir.406& SHU7DOWN Hof

~' \(o Ril5 c.

With both PORVs inoperable and incapable of RCS pressure control, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> either restore each of the PORVs to OPERABLE status or close their associated block valves and remove power from the block valves and be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and {GL4 SHUTDOWN withinl tie following~3& hours. hot Uo

d. With one or more block valve (s) inoperable, within I hour: (1) restore the block valve (s) to OPERABLE status, or close the block valve (s) and remove power f rom the block valve (s), or close the PORV(s) and remove power from its associated solenoid valve (s); and (2) apply the ACTION b, or c above, as appropriate, for the isolated PORV(s).

e, The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS-4.4.3.2.1 In addition to the requirements of Specification 4.0.5, each PORV shall be demonstrated OPERABLE at least once per 18 months by:

a. Performance of a CHANNEL CALIBRATION, and b.

by operating the valve through one complete cycle of full travels l

' cine,hg mode +.

4.4.3.2.2 Each block valve shall be demonstrated OPERABLE at least once per l

92 days by operating the valve through one complete cycle of full travel, SEQUOYAH - UNIT 1 3/4 4-4a Amendment No. 12, 105, 111 April 3, 1989 l

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REACTOR COOLANT SYSTEM RELIEF VALVES - OPERATING -

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LIMi7'NG CONDITION FOR OPERATION 3.4.3.2 All power operated relief valves (PORVs) and their associated block valves shall be OPERABLE.

APPLICABILITY: MODES 1, 2, and 3.

ACTION:

a. With one or more PORV(s) i.. operable, but capable of RCS pressure control, witnin 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> either restore the PORV(s) to OPERABLE status or close the associated block valve (s); otherwise, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in-EstG-SHUTDOWN within the following -30 hours. Hor Mo

b. With one PORV inoperable and incapable of RCS pressure control,

within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> either restore the PORV to OPERABLE status or close the associated block valve and remove power from the block valve; restore the PORV to OPERABLE status within the following 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in-Gets-SHUTCOWN within the following M hours. hot

c. With both PORVs inoperable and incapable of RCS pressure control, i within 1 heur either restore each of the PORVs to OPERABLE status or ,I close their associated block valves and remove power from the block valves and be in HOT STAND 8Y within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and-GL-G-(. ,

SHUTOOWN within the following M hours. McT R101

d. With one or more block valve (s) inoperable, within 1 hour:

(1) restore the block valve (s) to OPERABLE status, or close the block valve (s) and remove power from the block valve (s), or close the PORV(s) and remove power from its associated solenoid valve (s);

and (2) apply the ACTION b or c. above, as appropriate, for the isolated PORV(s).

e. The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS 4.4.3.2.1 In addition to the requirements of Specification 4.0.5, each PORY shall be demonstrateo OPERABLE at least once per 18 months by:

a. Performance of a CHANNEL CALIBRATION, and

b. Operating the valve through one complete cycle of full travelg duru13 mode 4..

4.4.3.2.2 Each block valve shall be demonstrated CPERA8LE at least once per .

92 days by operating the valve through one complete cycle of full travel. I SEQUOYAH - UNIT 2 3/4 4-8 Amendment No. 94,101 l April 3, 1989 l

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s REACT'OR COOLANT SYSTEM i

BASES safety-valves are OPERABLE, an operating RHR loop, connected to the RCS,

-provides overpressure relief capability and will prevent RCS overpressurization.

During operation, all pressurizer code safety valves must be OPERABLE to prevent the RCS from being pressurized above its safety limit of 2735 psig.

The combined relief capacity of all of these valves is greater than the maximum surge rate resulting from a complete loss of load assuming no reactor trip until the first Reactor Protective System trip set point is reached (i.e. , no credit is taken for a direct reactor trip on the loss of load) and also assuming no operation of the power operated relief valves or steam dump valves.

-Demonstr.

on of the safety valves' lift settings will occur only during shutdown and .. !) be perfotmed in accordance with the provisions of Section XI ,

of the ASME Boiler and Pressure Code.

The power operated relief valves (PORVs) and steam bubble function to relieve RCS pressure during all design transients vp to and including the design step loed decrease with steam dump. Operation of the PORVs minimizes the undesirable opening of the spring-loaded pressurizer code safety valves.

Each POR/ has a remotely operated block valve to provide positive shutoff capability should a relier valve become inoperable. The PORVs also function M to remove non condensibles or steam from the pressurizer. RI 4 (

3/4.4.4 PRESSURIZER79 SERT"@ ""

The limit on the maximum water volume in the pressurizer assures that the parameter is maintained within the normal steady state envelope of operation assumed in the SAR. The limit is consistent with the initial SAR assumptions.

The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> periodic surveillance is sufficient to ensure that the parameter is restored to within its limit following expected transient operation. The ,

maximum water volume also onsures tnat a steam bubble is formed and thus the RCS is not a hydraulically solid system. The requirement that 150 kw of pressurizer heaters and their associated controls be capable of being supplied electrical power from an emergency bus provides assurance that the plant will R16 be able to control reactor coolant pressure and establish natural circulation conditions.

3/4.4.5 STEAM GENERATORS The Surveillance Requirements for inspection of the ste' am generator tubes ensure that the structural integrity of this portion of the RCS will be maintained. The program for inservice inspection nf steam generator tubes is based on a modification of Regulatory-Guide 1.83, Revision 1. Inservice inspection of steam generator tubing is essential in order to maintain a surveillance of the conditions of the tubes in the event that there is evidence of mechanical damage or progressive degradation due to design, manufacturing errors, or it service conditions that . lead to corrosion. Inservice inspection of steam generator tubing also provides a means of characterizing the nature and cause of any tube degradation so that corrective measures can be taken.

SEQUOYAH - UNIT 1 B 3/4 4-2 Amendment No. 12, 133 March 22, 1990

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, . INSERT A-The OPERABILITY of the power-operated relief valves (PORVs) and block .

- valves is . determined on the : basis of their being capable of performing the following functions:' ,

p A.- Manual- control of PORVs to control reactor coolant system pressure.

This is a funetton that is used for~a steam generator tube rupture l-j accident.

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- B. Maintaining the integrity of the reactor coolant pressure boundary. ,

This is a function that is related to controlling identified leakage and' ensuring toe ability to detect unidentified reactor coolant

pressure boundary leakage.

1 C; Manusl; control of the block valve (1) unblock an isolated PORU to-

. 'ow it to be used for manual * '

of reactor coolant system t-

. pressure (Item A), and (2) is s "ith excessive seat leakage-l -(Item B).

D. Automatic control of PORVs to cv 'olant system pressure. This is a function tb :ges to the code safety = valves for~ overpressure es E. Manual control of a block valve to is, qqn PORV.

- Surveillance requirements (SR) provide assurance that the PORVs and block valves can perf orm their f unctions. The block valves are exempt from the SR to cycle the valves when-they nave been closed to comply with the l

ACTION requirements. This precludes the need to cycle the valves with-L -full. system differential pressure or when maintenance is being performed to restore an inoperable PORV to operable status.

Testing of PORVs in HOT SHUTDOWN is required in order to simulate the temperature and pressure environmental effects on PORVs. In many PORV designs, testing at COLD SHUTDOWN is not-considered to be a representative 1

' test-for assessing PORV performance under normal operating conditions. In l addition, testing PORVs in HOT SHUTDOWN =would provide added assurance of valve operability for low-temperature overpressure protection. -- t i

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e REACTOR COOL NT SYSTEM BRES 3/4.4.2 and 3/4.4.3 SAFETY AND RELIEF VALVES The pressurizer code safety valves operate to prevent the RCS from being pressurized above its Safety Limit of 2735 psig. Each safety valve is designed to relieve 420,000 lbs per hour of saturated steam at the valve set point.

The relief capacity of a single safety valve is adequate to relievo any over-pressure condition which could occur during shutdown. In the event that no safety valves are OPERABLE, an operating RHR loop, connected to the RCS, provides overpressure relief capability and will prevent RCS overpressurization.

During operation, all pressurizer code safety valves must be OPERABLE to prevent the RCS from being pressurized above its safety limit of 2735 psig.

The combined relief capacity of all of these valves is greater than the maximum surge rate resulting from a complete loss of load assuming no re"ctor trip l

untti the first Reactor Protect 1ve System trip set point is reached (i.e. , no l

credit is taken for a direct reactor trip on the loss of load) and also assuming I no operation of the power operated relief valves or steam dump valves.

Demonstration of the safety valves' lif t settings will occur only during shutdown and will be performed in accordance with the provisions of Section XI of the ASME Boiler and Pressure Code.

' The power operated relief valves (PORVs) and steam bubble function to

, relieve RCS pressure during all design transients up to and including the design step load decrease with steam dump. Operation of the PORVs minimizes the undesirable opening of the spring-loaded pressurizer code safety valves.

Each PORV'has a remotely operated block valve to provide positive shutoff capability should a relief valve become inoperable. The PORVs also function gi;o to remove non-condensibles or steam from the pressurizer.

% ~$MRT @

3/4.4.4 PRESSURIZER The limit on the maximum water volume in the pressurizer assures that the parameter is maintained _within the normal steady state envelope of operation assumed in the SAR. The limit is consistent with the initial SAR assumptions.

The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> periodic surveillance is sufficient to ensure that the parameter is restored to within its limit following expected transient operation. The maximum water volume also ensures that a steam bubble is formed and thus the RCS is not a hydraulically solid system. The requirement that 150 kw of pressurizer heaters and their associated controls be capable of being supplied electrical power from an emergency bus provides assurance that the plant will be able to control reactor coolant pressure and establish natural circulation conditions.

SEQUOYAH-bHIT2 8 3/4 4-2 Amendment No.120 March 22, 1990

.1NSERT A The OPERABILITY of the power-operated relief valves (PORVn) and block valves _is determined--on the basis of their being capable of performing the following functions:

A. . Manual control of PORVs to control reactor coolant system pressure.

This is a function that is used for a steam generator tube rupture accident.

B. Maintaining the integrity of the reactor coolant pressure boundary.

This is a function that is related to controlling identified leakage and ensuring the ability to detect unidentified reactor coolant pressure boundary leakage.

C. Manual control of the block valve to: -(1) unblock an isolated PORV to allow it to be used for manual control of reactor coolant system pressure (Item A), and (2) isolate a PORV with excessive seat leakage (Item B).

D. Automatic control of PORVs to control reactor coolant system pressure. This is a function that reduces challenges to the code

• safety valves for overpressure events.

E. Manual control of a block valve to isolate a stuck-open PORV.

Surveillance. requirements (SR) provide assurance-that the PORVs and block valves can perform their functions. The block valves arc exempt from the SR to cycle the valves when they have been closed to comply with the ACTION requirements. This precludes the need to cycle the valves with full system differential pressure or when maintenance is being performed to restore an inoperable PORV to operable status.

Testing of PORVs in HOT SHUTDOWN is required in order to simulate the temperature and-pressure environmental effects on-PORVs. In many PORV -

designs, testing at COLD SHUTDOWN is not considered to be a representative test for assessing PORV performance under normal operating conditions. In addition, testing FORVs in HOT SHUTDOWN would provide added assurance of valve operability for low-temperature overpressure protection, i

. ENCLOSURE.2 PROPOSED TECHNICAL SPECIFICATION CllANGE SEQUOYAH NUCLEAR PLANT UNITS-1 AND 2 DOCKET NOS.-50-327 AND 50-328.

(TVA-SQN-TS-91-13)

DESCRIPTION AND JUSTIFICATION FOR RELIEF VALVE ~ ACTION STATEMENTS AND SURVEILLANCE REQUIREMENTS 4"'

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Description of Change TVA proposes to modify the Sequoyah-Nuclear-Plant (SQN) Units 1 and 2 Technical-Specifications (TSs) 3/4.4.3 related to-the reactor-coolant system .

power-operated relief valves .(PORVs) and their associated block valves. The

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result of the proposed changes are-as follows:

1. The action statements a, b.-and e of limiting condition for operat' ion  ;

(LCO) '3.4.3.2 are being revised to terminate the forced-shutdown ,

requirements with the plant being in HOT SHUTDORN rather than COLD ,

SHUTDOWN.

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2. The PORV Surveillance Requirement (SR) 4.4.3.2.1(b) is being revised to include testing of PORVs during HOT SHUTDOWN (Mode 4).

3. Thebasesfor-thePORVandblockvalve(TSBasesSection3/4.4.3)are being expanded to identify the major functions of the FORVs and block >

valves. ,

Reason for Change ,

On July 25, 1990 NRC-issued Generic Letter (GL) 90-06, " Resolution of -

Generic !ssue 70, ' Power-operated Relief Valve and Block Valve Reliability,'

and Generic Issue 94, ' Additional Low-Temperatare Overpressure Protection for Light-Water Reactors ' Pursuant to 10 CFR 50.54(f)." This GL provided 1 the staff's pcsition regarding actions that should be taken to improve the i reliability of PORVs and block valves. The specific actions are described below:

1. Include PORVs and block valves in the quality assurance program in accordance with 10 CFR 50, Appendix B.

2. Include.PORVs, valves in PORV control air systems and block valves i L within the scope of the in-service testing (IST) program,

.3 . Modify TSs for PORVs. block valves, .and the low-temper ature overpressure. '

- protection system to incorporate various improvements that reflect the staff' position on"recent licensing. actions.

TVA's-reeponse to the GL dated December 21, 1990, addresses Items 1, 2, and 3 for SQN. In addition, TVA's December 1990 letter (see Enclosure 2, Item 2) contained a SQN commitment for submitting a TS change to include testing of PORVs while in Modes 3 or 4. The purpcse of this TS amendment is

, to fulfill the stated commitment for SQN.

Justification for Change

-GL 90-06 recommends that PORVs be cycled during Modes-3 or 4 in order to i accurately. simulate environmental effects on the valves. The basis for this recommendation is that testing during Mode 5 may not be a representative test . (simulate temperature .and pressure environmental ef fect) for assessing PORV performance under normal plant operating conditiens. GL 90-06 also recommends testing of PORVs in Modes 3 or 4 in order to provide added assurance of valve reliability before establishing conditions where the PORVs would be used for low-temperature overpressure protection.

SQN's American Society of Mechanical Engineers (ASME)Section XI IST program t

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l currently requires = the PORVs to be cycled and timed quarterly during cold shutdown. It should'be_noted that SQN's IST procedure (Surveillance ,

Instruction {SI).166, "Suanmary of Valve Tests for ASME Seation XI," Part A) '

does allow testing to be performed.in Mode 4; however, Mode 5 testing-is  ;

preferred since:the associated block valve remains in the open position while the PORV is cycled. A-separate procedure (SI-5XV-068-001.0) satisfies -

the cur *ent TS SR 4.4.3.2.l(b) that requires each PORV to be demonstrated operable once every 18 months by operating the valve through one complete cycle of fu?1 travel. This test cycles each PORV in either Modes 4 or 5 while the reactor coolant system pressure is sufficiently high (300 pounds per square inch, gauge or greater) to induce a blowdown of reactor coolant ,

system fluid through the PORV. This methodolcgy provides an indirect means  !

of= confirming valve operation and valve position since SQN's PORVs are

totally enclosed solenoid valves (limit switches cannot be visually verified at the. valve). Valve operation is confirmed by monitoring chanBes in temperature downstreara of the PCRVs following valve manipulation.

Performance of this test.also satisfies the 2-year ASME code requirement to verify that remote valve indication (red and green lights in the main I control room) accurately reflect valve operation.

IVe proposes to revise SR 4.4.3.2.l(b) to require exercising PORVs in Mode 4. The provision to allow testing PORVs in Mode 3 was not included in TVA's proposed TS enange. The optico for exercising PORVs in Mode 3 (i.e.,

, full reactor coolant system pressure and temperature) has the potential for-rapid depressurization of the pressurizer resulting in a safety-injection signal. Because of the r!.sk of inducing a plant transient, TVA proposes not to include the option for testing PORVs in Mode 3. TVA intends to retain the currer. test methodology for exercising PORVs in Mode 4 with the block valves-open. The proposed change would thereby comply with the recernendations of the-GL 90-06.

In addition to the proposed change to SR 4.4.3.2.l(b) TVA is including a suggested improvement for consistency to the ACTION statements a b, and c of SQN LCO 3.4.3.2. 1hese ACTION statements are being revtsed to terminate the forced-shutdown requirements with the plant being in HOT SHUTDORN rather than COLD SHUIDOWN. The proposed change will make the forced-shutdown requirements consistent with the APPLICABILITY requirements _since the APPL 1CABILITY requirements of the LCO do not extend past the HOT STANDBY mode. The shutdcon time _ requirements fvr placing the plant in HOT SHUTDOWN cather than COLD SHUTDOWN tave keen amended from 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. These

• changes are based on the guidance provided by Item 4 on page A-9 of GL 90-06 and the Modified Standard Technical Specifications on page A-4 In conclusion, TVA proposes to modify SQN TSs to comply with GL 90-06 for testing PORVs in Mode 4 and for terminating forced-shutdown requirements in

-HOT 5HUTDOWN rather than COLD SHUTDOWN.

Environmental Impact Evaluation The proposed change request does not involve an unreviewed environmental question because operatien of SQN Units I and 2 in accardance with this change would not:

1. Result in a significant increase in any adverse environmental impact

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-previously evaluated in the Final. Environmental Statement (FES) as -

modified by the staff's testimony to the Atomic Safety and Licensing.

Board, supplements to the FES, environmental' impact appraisals, or--

decisions of the Atomic Safety'and Licensing Board..

2, Result-in a significant change in effluents or power levels.

3. Result in matters not previously reviewed in the licensing basis for SQN that may have a significant environmental impact.

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-s Enclosure 3 PROPOSED-TECIINICAL SPECIFICATION CHANGE-

- SEQUOYAll NUCLEAR PLANT LHITS 1 AND 2 DOCKET NOS. 50-327.AND 50-328 (TVA-SQN-TS-91-13)

DETERMINATION OF NO SIGNIFICAM riAZARDS CONSIDERATION 2

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, e Significant Bazards Evaluation j i

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TVA has evaluated the proposed technical specification (TS) change and has '!

determined that it.does not represent a significant hazards consideration based on criteria established in 10 CFR 50.92(c). Operation of Sequoyah  ;

Nuclear Plant (SQN) in accordance with the proposed amendment will not: 1

1. -Involve a significant increase in the probability or consequences of an accident previously evaluated.

From an accident and; transient mitigation standpoint, SQN's powcr-cperated relief valves (PORVs) can be utillred to perform several safety-related functions. These include mitigation of a steam generator (SG) tube rupture accident and low-temperature overpressure protection 3 oi-the reactor vessel. In addition, the PORVs can be an accident initiator in the case where a failed-open-PORV results in a s.aall break loss-of coolant accident.

Under normal operating conditions, SQN's PORVs are designed to limit pressurizer pressure and prevent the undesirable opening of the p pressurizer safety valves. The PCRVs are also used for automatic and manual pressure control. The Final Safety Analysis Report analysis for overpressure protection in Modes 1, 2 and 3 assumes that the PORVs do not~ actuate. The pressurizer safety valves provide the required pressure relief.

TVA's proposed change adds surveillance testing of the PORVs in Mode 4 The intent-of requirfng PORVs to be tested during Mode 4 is to '

a demonstrate operability of the PORVs between power. operational modes (Modes 1 and 2) and Slode-5 when the plant is most vulnerable to a low-temperature overpressure transient. The proposed change remains consistent with the guidance provided in GL 90-06 and continues to provide operability assurance that SQN's PORVs will perform their safety-related' functions.

TVA's proposed change to the ACTION statements for terminating a forced-shutdown at HOT SHUTLOKN rather than COLD SHUTDOWN provides consistency.between the applicability requirements.cf the limiting condition of operation (LCO)'and the forced-shutdown requirements. This change is considered to be an improvement for maintaining consistent LCO applicability and shutdown requirements within T$s. Accordingly, the '

proposed change does not sigulficantly increase the probability er consequences of an accident previously evaluated.

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2. Create the possibility of a new or different kind of accident from any-F previously analyzed.

The change to the subject surveillance requirement for testing P7RVs in Mode 4 does not require any hardware changes. Existing surveillance instructions at SQN allow for testing PORVs while in Mode 4. The changes associnted with the ACTION statements follow the guidance of GL 90-06 for providing consistency between forced-shutdown requirem~e nts and LCO applicability requirements. Thus the possibility of a new or different kind of accident is not creeted.

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-3. Involve a significant reduction in a trargin of safety.

The intended design and operation of SQN's PORVs have not been changed.

The safety-related functions of the'PORVs (i.e., mitigation of.a SG tube rupture and low-temperature overpressure protection) remain unchanged.

Testing the FORVs in Mode 4 provides additional inssurance of valve operability for' performing safety-related functions. The additional changes associated with ACTION statements a. b, and c provide a TS improvement by establishing consistency between the LCO applicability requirements and the f orced-shutdown requi rements. Accordingly, the margin of safety has not been changed.

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