ML20073C791

Proposed Tech Specs,Revising TS SR 4.7.4.e & Associated Bases Section 3/4.7.4 to Extend Snubber Functional Testing Interval from 18 Months to 24 Months to Increase Sample Plan Size

ML20073C791
Person / Time
Site:	Limerick
Issue date:	09/16/1994
From:	PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:
Shared Package
ML20073C784	List: ML20073C781 ML20073C791
References
NUDOCS 9409260165
Download: ML20073C791 (4)

Text

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ATTACHMENT 2  !

t UMERICK GENERATING STATION  ;

UNITS 1 AND 2 ,

i Docket Nos. 50-352 50-353 Ucense Nos. NPF-39 NPF-85 {

i TECHNICAL SPECIFICATIONS CHANGE REQUEST i No. 94-50-0 .,

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UST OF AFFECTED PAGES Unit 1 Unit 2  ;

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3/4 7-13 3/4 7-13 B 3/4 7-3 B 3/4 7-3 i

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9409260165 PDR 940916 l ADOCK 05000352 l PDR l

PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

e. Functional Tests At least once per 24 months a representative sample of each type of l snubber shall be tested using the following sample plans. The sample plan (s) shall be selected for each type prior to the test period and cannot be changed during the test period. The NRC Regional Administrator shall be notified in writing of the sample plan (s) selected for each type prior to the test period or the sample plan (s) used in the prior test period shall be implemented:

1) At least 13.3% of the total population of a snubber type shall be l functionally tested. For each snubber of that type that does not meet the functional test acceptance criteria of Specification 4.7.4f., an additional sample of at least 1/2 the size of the initial sample shall be tested until the total number tested is equal to the initial sample multiplied by the factor,1+C/2, where C is the total number of unacceptable snubbers or until all the snubbers of that type have been tested; or

2) A representative sample of 37 snubbers of a snubber type shall be functionally tested in accordance with Figure 4.7.4-1. "C" is the total number of snubbers of that type found not meeting the acceptance requirements of Specification 4.7.4f. The cumulative number of snubbers of the type tested is denoted by "N". If at any time the point plotted falls in the " Accept" region, testing of snubbers of that type may be terminated. When the point plotted lies in the " Continue Testing" region, additional snubbers of that type shall be tested until the point falls in the " Accept" region, or all the snubbers of that type have been tested.

LIMERICK - UNIT 1 3/4 7-13

PLANT SYSTEMS BASES SNVBBERS (Continued)

To provide assurance of snubber functional reliability one of two functional testing methods is used with the stated acceptance criteria:

1. Functionally test 13.3% sample of a type of snubber with an additional 1/2 sample tested for each functional testing failure, or

2. Functionally test 37 snubbers and determine sample acceptance using Figure 4.7.4-1.

Functional Testing sample plans are based on ASME/ ANSI OMc-1990 Addenda to ASME/ ANSI OM-1987, Part 4.

Figure 4.7.4-1 was developed using "Wald's Sequential Probability Ratio Plan" as described in Quality Control and Industrial Statistics" by Acheson J. Duncan.

Permanent or other exemptions from the surveillance program for individual snubbers may be granted by the Commission if a justifiable basis for exemption is presented and, if applicable, snubber life destructive testing was performed to qualify the snubbers for the applicable design conditions at either the completion of their fabrication or at a subsequent date. Snubbers so exempted shall be listed in the list of individual snubbers indicating the extent of the exemptions.

The service life of a snubber is evaluated via manufacturer input and information through consideration of the snubber service conditions and associated installation and maintenance records (i.e., newly installed snubber, seal replaced, spring replaced, in high radiation area, in high temperature area, i etc.). The requirement to monitor the snubber service life is included to ensure  !

that the snubbers periodically undergo a performance evaluation in view of their i age and operating conditions. These records will provide statistical bases for i future consideration of snubber service life. I 3/4.7.5 SEALED SOURCE CONTAMINATION The limitations on removable contamination for sources requiring leak testing, l including alpha emitters, is based on 10 CFR 70.39(c) limits for plutonium. This i limitation will ensure that leakage from byproduct, source, and special nuclear ,

material sources will not exceed allowable intake values. Sealed sources are l classified into three groups according to their use, with surveillance requirements commensurate with the probability of damage to a source in that group. Those sources which are frequently handled are required to be tested more often than those which are not. Sealed sources which are continuously enclosed within a shielded mcchanism, i.e., sealed sources within radiation monitoring devices, are considered to be stored and need not be tested unless they are removed from the shielded mechanism.

LIMERICK - UNIT 1 B 3/4 7-3

PLANT SYSTEMS SURVEILLANCE RE0VIREMENTS (Continued)

e. Functional Tests At least once per 24 months a representative sample of each type of l snubber shall be tested using the following sample plans. The sample plan (s) shall be selected for each type prior to the test period and cannot be changed during the test period. The NRC Regional Administrator shall be notified in writing of the sample plan (s) selected for each type prior to the test period or the sample plan (s) used in the prior test period shall be implemented:

1) At least 13.3% of the total population of a snubber type shall be l functionally tested. For each snubber of that type that does not meet the functional test acceptance criteria of Specification 4.7.4f., an additional sample of at least 1/2 the size of the initial sample shall be tested until the total number tested is equal to the initial sample multiplied by the factor,1+C/2, where C is the total number of unacceptable snubbers or until all the snubbers of that type have been tested; or

2) A representative sample of 37 snubbers of a snubber type shall be functionally tested in accordance with Figure 4.7.4-1. "C" is the total number of snubbers of that type found not meeting the acceptance requirements of Specification 4.7.4f. The cumulative number of snubbers of the type tested is denoted by "N". If at any time the point plotted falls in the " Accept" region, testing of snubbers of that type may be terminated. When the point plotted lies in the " Continue Testing" region, additional snubbers of that type shall be tested until the point falls in the " Accept" region, or all the snubbers of that type have been tested.

LIMERICK - UNIT 2 3/4 7-13

PLANT SYSTEMS BASES SNUBBERS (Continued)

To provide assurance of snubber functional reliability one of two functional testing methods is used with the stated acceptance criteria:

1. Functionally test 13.3% sample of a type of snubber with an additional 1/2 sample tested for each functional testing failure, or

2. Functionally test 37 snubbers and determine sample acceptance using Figure 4.7.4-1.

Functional Testing sample plans are based on ASME/ ANSI OMc-1990 Addenda to ASME/ ANSI OM-1987, Part 4.

Figure 4.7.4-1 was developed using "Wald's Sequential Probability Ratio Plan" as described in Quality Control and Industrial Statistics" by Acheson J. Duncan.

Permanent or other exemptions from the surveillance program for individual snubbers may be granted by the Commission if a justifiable basis for exemption is presented and, if applicable, snubber life destructive testing was performed to qualify the snubbers for the applicable design conditions at either the completion of their fabrication or at a subsequent date. Snubbers so exempted shall be listed in the list of individual snubbers indicating the extent of the exemptions.

The service life of a snubber is evaluated via manufacturer input and information through consideration of the snubber service conditions and associated installation and maintenance records (i.e., newly installed snubber, seal replaced, spring replaced, in high radiation area, 4 high temperature area, etc.). The requirement to monitor the snubber service life is included to ensure that the snubbers periodically undergo a performance evaluation in view of their age and operating conditions. These records will provide statistical bases for future consideration of snubber service life.

3/4.7.5 SEALED SOURCE CONTAMINATION The limitations on removable contamination for sources requiring leak testing, ,

including alpha emitters, is based on 10 CFR 70.39(c) limits for plutonium. This 1 limitation will ensure that leakage from byproduct, source, and special r.uclear  ;

material sources will not exceed allowable intake values. Sealed sources are  ;

classified into three groups according to their use, with surveillance requirements commensurate with the probability of damage to a source in that group. Those sources which are frequently handled are required to be tested more often than those which are not. Sealed sources which are continuously enclosed within a shielded mechanism, i.e., sealed sources within radiation monitoring devices, are considered to be stored and need not be tested unless they are removed from the shielded mechanism.

l LIMERICK - UNIT 2 B 3/4 7-3 l