NUREG- 1552, Supp. 1

Fire Barrier Penetration Seals

in Nuclear Power Plants

U.S. Nuclear Regulatory Commission

Office of Nuclear Reactor Regulation
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NUREG-1552, Supp. 1

Fire Barrier Penetration Seals

in Nuclear Power Plants

Manuscript Completed: December 1998

Date Published: January 1999

C. S. Bajwa, K. S. West

Division of Systems Safety Analysis

Office of Nuclear Reactor Regulation

U.S. Nuclear Regulatory Commission

Washington, DC 20555-0001

ABSTRACT

In NUREG-1552, "Fire Barrier Penetration Seals in

Nuclear Power Plants," the U.S. Nuclear Regulatory

Commission staff documented the results of its

comprehensive technical assessment of penetration

seals. Subsequently, the staff assessed new

information for new insights. The results of the

updated assessment are documented in this report.

Nuclear power plants use the "defense in depth"

concept of echelons of fire protection to achieve a

high degree of fire safety. Fire barrier penetration

seals, which are one element of the fire protection

defense-in-depth concept, are designed to confine a

fire to the area in which it started or to protect plant

systems and components within an area from a fire

outside the area. For the reasons given in this report,

it is the staff's judgment that, generically, typical

penetration seal deficiencies do not equate to a lack

of adequate protection or result in undue risk to

public health and safety. It is the staff's opinion that

continued licensee attention to existingpenetration

seal programs and continued NRC reviews and

inspections are adequate to (1) provide reasonable

assurance that penetration seal problems are

discovered and resolved and (2) maintain public

health and safety.

iii iii NUREG-1552, Supp. I

TABLE OF CONTENTS

Page

A B STR A C T ................................................................................ iii

EXECUTIVE SUM M ARY ................................................................... vii

DEFENSE-IN-DEPTH CONCEPT AND THE ROLE OF PENETRATION SEALS ................ I

1.1 Assessments of Fire Barrier Penetration Seals .......................................... 1

1.2 The Role of Penetration Seals in the Defense-in-Depth Concept ........................... 1

2 REVIEW OF REACTOR OPERATING EXPERIENCE ...................................... 3

2.1 Licensee Event Reports ........................................................... 3

2.2 N R C Inspections ................................................................ 4

2.3 Fire Experience ................................................................. 5

2.4 Summary of Operating Experience .................................................. 6

3 SAFETY SIGNIFICANCE ............................................................. 6

3.1 Fire Protection Program ............................................................ 6

3.2 Safety Significance Ranking of Penetration Seal Deficiencies ............................. 7

3.3 Generic Assessment of Safety Significance ............................................ 7

3.3.1 Improperly Installed or Degraded Seals and Inadequate Documentation ................ 8

3.3.2 Unsealed and Breached Penetrations ........................................... 9

3.4 Seal-Specific Assessment of Safety Significance ....................................... 10

4 RISK SIGNIFICANCE ............................................................... I I

5 COMPENSATORY MEASURES ...................................................... 11

6 PLANT-SPECIFIC EXPERIENCE WITH FIRE BARRIER PENETRATION SEALS ............. 11

6.1 Vermont Yankee Nuclear Power Station ............................................. 11

6.2 W olf Creek Nuclear Generating Station ............................................. 12

6.2.1 Operating Experience ...................................................... 12

6.2.2 01 Investigation ........................................................... 12

6.3 Salem Nuclear Generating Station .................................................. 13

6.4 M illstone Nuclear Power Station ................................................... 13

6.5 M aine Yankee Atomic Power Plant ................................................. 13

6.5.1 NR C Inspection ........................................................... 13

6.5.2 Licensee Event Reports .................................................... 14

6.5.3 Staff Follow up ............................................................ 14

6.5.4 Conclusions on Maine Yankee Operating Experience ............................. 15

6.6 C onclusions ................................................................... 15

7 REVIEW OF PLANT-SPECIFIC LICENSING BASES RELATED TO SECTION III.M

OF APPENDIX R TO 10 CFR PART 50 ................................................. 15

7.1 Introduction ................................................................... 15

7.2 Plant-Specific Licensing Bases .................................................... 16

7.2.1 Calvert Cliffs Nuclear Power Plant, Units 1 and 2 ............................ 16

7.2.2 Duane Arnold Energy Center ............................................ 16

7.2.3 James A. FitzPatrick Nuclear Power Plant .................................. 17

7.2.4 Maine Yankee Atomic Power Plant ....................................... 17

7.2.5 Monticello Nuclear Generating Plant ...................................... 17

7.2.6 Peach Bottom Atomic Power Station, Units 1 and 2 ........................... 17

7.2.7 Pilgrim Nuclear Power Station, Unit I ..................................... 17

v NUREG-1552, Supp. 1
Table of Contents

Page

7.2.8 Point Beach Nuclear Plant, Units I and 2 ................................... 18

7.2.9 H.B. Robinson Steam Electric Plant, Unit 2 ................................. 18

7.2.10 Surry Power Station, Units 1 and 2 ........................................ 18

7.2.11 Vermont Yankee Nuclear Power Station ................................... 18

7.3 Sum m ary ..................................................................... 19

8 RECOMMENDATIONS IN THE FINAL STAFF REPORT ................................. 19

8.1 Introduction ................................................................... 19

8.2 Status ........................................................................ 19

8.2.1 Recommendations 1, 2, and 3 (Pending) .................................... 19

8.2.2 Recommendation 4 (Complete) ........................................... 20

8.2.3 FPFI Program (Complete) ............................................... 20

9 PUBLIC COMMENTS ON DRAFT NUREG-1552, SUPPLEMENT 1 ......................... 20

10 CON CLUSION S .................................................................... 20

APPENDICES*

D Acronyms and Abbreviations ............................................................. D-1

F Licensee Event Reports Submitted by Year (1987 Through September 1998) ........................ F-1

G Summary of Reported Problems (1987 Through September 1998) ............................... G-1

H Summary of Licensee Event Reports (1987 Through September 1998) ............................ H-1

I NRC Inspections (March 1988 Through August 1998) ........................................ I-1

J Plants Known To Have Performed 100-Percent Penetration Seal Inspections ........................ J-1

K Reference Summ ary ................................................................... K-1

*Appendices A-E appear in NUREG-1552.

NUREG-1552, Supp. 1 vi
EXECUTIVE SUMMARY

Nuclear power plants use the "defense in depth"

concept of echelons of fire protection to achieve a

high degree of fire safety. The objective of this

concept is to (1) prevent fires from starting;

(2) rapidly detect, control, and extinguish those fires

that do occur; and (3) protect structures, systems, and

components important to safety so that a fire that is

not promptly extinguished will not prevent the safe

shutdown of the plant. The multiple layers of fire

protection provided by the defense-in-depth concept

offer reasonable assurance that weaknesses or

deficiencies in one layer will not present an undue

risk to public health and safety.

Fire barriers, which are one element of the fire

protection defense-in-depth concept, accomplish their

intended design function simply by remaining in

place during a fire. They are important because they

are the first and also the last lines of defense against

a fire. That is, during the early stages of a fire, the

barriers confine the fire and protect important

systems and components until the fire detection and

automatic fire suppression systems operate. In

addition, in the event that an automatic fire protection

system fails to operate or fire brigade response is

delayed, the fire barriers continue to provide passive

fire protection. Fire barrier penetration seals are

another element of defense in depth and, like the

structural fire barriers in which they are installed, are

passive fire protection features. Their design

function is to confine a fire to the area in which it

started or to protect plant systems and components

within an area from a fire outside the area. Fire

barrier penetration seals are not safety related.

Between 1994 and 1996, the Office of Nuclear

Reactor Regulation (NRR) staff conducted a

comprehensive technical assessment of penetration

seals to address reports of potential problems, to

determine if there were any problems of safety

significance, and to determine if NRC requirements,

review guidance, and inspection procedures were

adequate. The staff did not find any plant-specific

problems of safety significance or any concerns with

generic implications. The staff concluded that the

general condition of penetration seal programs in

industry was satisfactory. The staff also concluded

that the information notices it had issued in 1988 and

1994, increased industry awareness of potential

penetration seal problems and resulted in more

comprehensive surveillance activities, maintenance

practices, and corrective actions on the part of

industry. The staff concluded that these actions

together with continued NRC inspections, and

continued licensee attention to existing penetration

seal programs, were adequate to maintain public

health and safety. The staff documented its

assessment in SECY-96-146, "Technical Assessment

of Fire Barrier Penetration Seals in Nuclear Power

Plants" (July 1, 1996), and NUREG-1552, "Fire

Barrier Penetration Seals in Nuclear Power Plants"

(July 1996).

The NRC staff has since continued to review

potential penetration seal problems on a case-by-case

basis as they are found or reported. This report

supplements the NRC staff assessment of fire barrier

penetration seals by reviewing additional information

on seal problems reported by licensees and found

during NRC inspections performed prior to as well as

since the assessment documented in SECY-96-146

and NUREG-1552. In light of the new information,

the staff reconsidered the operating experience

reported in NUREG-1552, and considered the results

of the effort, as documented in this report, for

insights and appropriate opportunities for actions by

the NRC and the industry.

As part of this reassessment, the staff reviewed

previous NRC inspections of penetration seal

programs. Between 1988 and March 1998, it

conducted 153 inspections that involved installed

penetration seals and penetration seal programs at 87

plants. In general, the inspectors found that the

penetration seal programs were comprehensive,

timely, and acceptable. In some cases, the inspectors

found deficiencies and issued notices of violations.

These inspections are summarized in Appendix I. In

addition, the staff obtained the licensee event reports

(LERs) on fire barrier penetration seals that were

submitted in 1987, 1988, and 1994 through

September 1998, inclusive. The staff also reviewed

LERS that were submitted from 1989 through 1993

for a second time. (The staff originally documented

the results of its review of these LERs in NUREG1552.) The staff found that 9 plant sites submitted 16

LERs during 1987; 12 plant sites submitted 19 LERs

during 1988; and 14 plant sites submitted 34 LERs

between 1994 and September 1998. Appendix F

shows the numbers of LERs and LER supplements

regarding fire barrier penetration seals that were

submitted by year from January 1987 through

September 1998. Appendix G details the types of

problems (the four major categories and

vii NUREG-1552, Supp. 1
Executive Summary

subcategories) that were reported by year for the

same period, and the number of times the problems

occurred. Appendix H reports on each LER and LER

supplement that the staff considered during this

reassessment of penetration seals. This report also

contains a detailed review of the status of penetration

seal programs at several plants that have undertaken

major corrective action programs for penetration

seals.

Section III.M of Appendix R to 10 CFR Part 50

specifies that penetration seals utilize only

noncombustible materials. To address questions

about the NRC regulatory requirements regarding the

use of these penetration seal materials, the staff

reviewed the fire protection licensing basis for all

nuclear plants. The staff determined which plants are

required to comply with Section III.M of Appendix R

to 10 CFR Part 50. The staff then conducted a

detailed review of the fire protection licensing bases

for those units to determine if the plants used

silicone-based fire barrier penetration seal materials

and, if they did, how the licensees and the staff

addressed the regulatory requirement of

Section III.M of Appendix R.

On the basis of everything it identified and

considered, the staff judges that, overall, the issue of

potential fire barrier penetration seal deficiencies is

not a safety concern. For the reasons given in this

report, typical penetration seal deficiencies do not

necessarily equate to inadequate protection or result

in undue risk to public health and safety.

On the basis of the reassessment documented here,

the staff concludes that the actions it took in 1988

and 1994 to alert licensees to potential penetration

seal problems increased industry awareness of such

problems and resulted in more comprehensive

surveillance activities, maintenance practices, and

corrective actions. The staff also concludes that the

general condition of penetration seal programs in

industry appears to be satisfactory. The staff expects

that plant-specific deficiencies may occasionally be

found during licensee surveillances and NRC

inspections. However, potential penetration seal

problems are understood; industry consensus fire test

standards are available and are complied with; and

fire test results and qualified fire-resistant seal

materials and designs are available. Therefore,

licensees have the means to correct problems, and

continued staff oversight will ensure that corrections

are made on a case-by-case basis.

In summary, it is the staff's opinion that continued

licensee attention to existing penetration seal

programs and continued NRC inspections are

adequate (1) to ensure that penetration seal problems

are discovered and resolved and (2) to maintain

public health and safety.

To provide added assurance of this, during the

assessment documented in this report, the staff issued

Information Notice 97-70, "Potential Problems With

Fire Barrier Penetration Seals," September 19, 1997,

and revised the NRC fire protection core inspection

module to provide more specific inspection guidance

to NRC inspectors regarding fire barriers and fire

barrier penetration seals. The staff will continue to

assess new information regarding penetration seals

for new insights and appropriate opportunities for

additional actions by the staff or the industry.

During the 454th meeting of the Advisory Committee

on Reactor Safeguards (ACRS), July 8-10, 1998, the

staff presented the results of the assessment

documented in this supplement to NUREG-1552 to

the ACRS. The ACRS provided its views regarding

the efforts of the NRC staff and the nuclear industry

to resolve issues related to fire barrier penetration

seals in a letter of July 20, 1998, from R.L. Seale,

Chairman, ACRS, to Chairman Jackson. The ACRS

found it clear that, overall, the NRC staff and the

licensees have the issues of fire barrier penetration

seals well in hand and that the efforts of the staff and

the licensees have been successful in addressing the

problems of the past.

NUREG-1552, Supp. I viii
1 DEFENSE-IN-DEPTH

CONCEPT AND THE ROLE

OF PENETRATION SEALS

1.1 Assessments of Fire Barrier

Penetration Seals

Over the years, the U.S. Nuclear Regulatory

Commission (NRC) staff has completed a number of

assessments of fire barrier penetration seals. In 1987

and 1988, the Office of Nuclear Reactor Regulation

(NRR) and regional office staff performed a

comprehensive assessment of fire barrier penetration

seals. Although it found no widespread problems or

safety-significant generic issues, the staff alerted

industry to potential problems by means of a series of

information notices. Later, in 1993, NRR staff

reassessed the fire protection program for nuclear

reactors. In its "Report on the Reassessment of the

NRC Fire Protection Program" (February 27, 1993),

the staff concluded that licensees were complying

with regulatory requirements and that there were no

major or recurring issues with penetration seals. In

1995, the Office for the Analysis and Evaluation of

Operational Data (AEOD) reviewed fire barrier

penetration seals and reached many of the same

conclusions that NRR had reached. Finally, between

1994 and 1996, NRR staff conducted a

comprehensive technical assessment of penetration

seals to address reports of potential problems, to

determine if there were any problems of safety

significance, and to determine if NRC requirements,

review guidance, and inspection procedures are

adequate. The staff did not find any safetysignificant plant-specific problems or concerns with

generic implications. The staff concluded that the

general condition of penetration seal programs in the

nuclear industry was satisfactory. The staff also

concluded that the information notices it had issued

in 1988 and 1994 increased industry awareness of

potential penetration seal problems and resulted in

more comprehensive surveillance activities,

maintenance practices, and corrective actions.

Moreover, the staff concluded that these staff

actions, together with continued licensee attention to

existing penetration seal programs and continued

NRC inspections, were adequate to maintain public

health and safety. The staff documented its

assessment in SECY-96-146, "Technical Assessment

of Fire Barrier Penetration Seals in Nuclear Power

Plants" (July 1, 1996), and NUREG-1552, "Fire

Barrier Penetration Seals in Nuclear Power Plants"

(July 1996).

Notwithstanding these findings, the NRC staff

reviews potential problems on a case-by-case basis as

they are found or reported. Therefore, the NRC staff

updated its assessment of fire barrier penetration

seals by assessing information on seal problems

reported by licensees and found during NRC

inspections since the assessment documented in

SECY-96-146 and NUREG-1552. The staff

reconsidered the operating experience reported in

NUREG-1552 in light of the new information, and

also considered the results of this effort, which is

documented herein, for insights and appropriate

opportunities for actions by the NRC and the

industry.

1.2 The Role of Penetration Seals

in the Defense-in-Depth

Concept

Nuclear power plants use the "defense in depth"

concept of echelons of fire protection to achieve a

high degree of fire safety. The objective of the

concept is to (1) prevent fires from starting;

(2) promptly detect, control, and extinguish those

fires that do occur; and (3) protect structures,

systems, and components important to safety so that a

fire that is not promptly extinguished will not prevent

the safe shutdown of the plant. The several layers of

fire protection produced by the defense-in-depth

concept offer reasonable assurance that weaknesses

or deficiencies in one layer will not present an undue

risk to public health and safety. To achieve defense

in depth, each operating reactor maintains an NRCapproved fire protection program. The licensees

have designed the fire protection programs by

analyses that (1) considered potential fire hazards,

(2) determined the effects of fires in the plant on the

ability to safely shut down the reactor or on the

ability to minimize and control the release of

radioactivity to the environment, and (3) specified

measures for fire prevention, fire confinement, fire

detection, automatic and manual fire suppression,

and post-fire safe-shutdown capability.

Nuclear power plants are divided into separate areas

by structural fire barriers such as concrete floors,

walls, and ceilings. The fire protection function of

these barriers is to prevent a fire that starts in one

plant area from spreading to another area. A barrier's

fire-resistance rating, which is a measure of the

extent to which the barrier resists the effects of fire,

is determined by exposing a mockup of the barrier to

an intense test fire for a designated period. Nuclear

I NUREG-1552, Supp. 1
Defense-in-Depth Concept and the Role of Penetration Seals

power plant fire barriers typically have a fireresistance rating of 1, 2, or 3 hours. Openings are

needed in structural fire barriers to allow such items

as cable trays, conduits, pipes, and ventilation ducts

to pass from one plant area to another. To maintain

the fire protection function of the structural fire

barriers, the openings and the gaps and annular

spaces around the penetrating items (penetrations)

should be sealed in a configuration that offers the

same fire resistance as that of the barrier in which

they are installed. The average number of fire barrier

penetration seals per nuclear power plant unit is

about 3000 and a single unit can have up to 10,000

seals.

Fire barriers, which are one element of the fire

protection defense-in-depth concept, accomplish their

intended design function simply by remaining in

place during a fire. They are important because they

may serve as the first and also the last lines of

defense against a fire. That is, during the early stages

of a fire, the barriers confine the fire and protect

important systems and components until the fire

detection and automatic fire suppression systems

operate. In addition, in the event that an automatic

fire protection system fails to operate or fire brigade

response is delayed, the fire barriers continue to

provide passive fire protection. Fire barrier

penetration seals are another element of defense in

depth and, like the structural fire barriers in which

they are installed, are passive fire protection features.

Their design function is to confine a fire to the area

in which it started or to protect plant systems and

components within an area from a fire outside the

area.

To gain reasonable assurance that a penetration seal

will have the required fire-resistance capability or

fire rating, a penetration seal test assembly is

subjected to a fire endurance test. The test methods

involve the furnace-fire exposure of a full-scale

penetration seal test specimen that is representative

of the construction for which a fire-resistance rating

is desired. The heat input to the test furnace is

controlled so that the average temperature in the

furnace follows the time-temperature curve specified

in the test standard. In the United States, the

standards for testing penetration seals use the timetemperature curve defined in American Society for

Testing and Materials (ASTM) E- 119, "Standard

Test Methods for Fire Tests of Building Construction

and Materials'." This time-temperature curve, which

is used to determine the fire resistance of all types of

building fire barriers, represents a severe fire

exposure. (It is important to note that fire tests are

not intended to model any specific room fire or the

conditions under which the seals will be exposed

during a fire, but rather to provide a specific standard

fire exposure against which similar fire rated

assemblies can be evaluated.)

The fire protection effectiveness of structural fire

barriers is largely dependent on their inherent fire

resistance, details of construction, and protection of

penetrations. Some fire barriers (both structural

barriers and penetration seals) are more important to

the fire protection defense-in-depth concept than

others. The importance of specific fire barriers

depends on many factors, such as the importance of

the plant systems and components in the fire area

(and adjacent areas); the types, amounts,

configurations, and locations of combustible

materials and fire hazards, if any, in the areas; the

potential for fire growth in the areas; the fire

protection features installed in the areas; and the

accessibility of the areas to the plant fire brigade.

The importance of specific penetration seals depends

on these factors and on such other factors as their

size, their location or position in the fire barrier, and

the number and sizes of the other seals in the barrier.

In order of overall importance to fire protection

defense in depth, structural fire barriers, being

necessary for the structural integrity of a building or

fire area, are generally considered to be more

important than fire barrier penetration seals.

Qualified fire protection engineers determine the

importance of individual fire barriers by analyzing

fire hazards and the locations of safe shutdown and

safety-related systems and components.

Although a detailed discussion of such analyses is

beyond the scope of this paper, the following

discussion illustrates this approach.

Consider, for purposes of a worst-case analysis, that

a structural fire barrier fails during exposure to a fire.

In this event, the adjoining fire area and its contents

would be exposed to the same fire and would,

themselves, become involved in the fire in a short

'Representative points on the curve that determine its

character are: 1000 'F at 5 minutes, 1550 OF at

30 minutes, 1700 *F at 1 hour, 1850 *F at 2 hours,

and 1938 *F at 3 hours.

NUREG-1552, Supp. 1 2
Review of Reactor Operating Experience

period of time. (Because of the substantial

construction of structural fire barriers in nuclear

power plants and fire protection defense in depth, the

staff does not consider this a credible nuclear power

plant fire scenario.) Similarly, catastrophic failure of

a penetration seal could expose the adjacent fire area

to the fire. However, since the penetration seal is not

necessary for structural integrity, its failure is not as

significant a fire threat as the failure of a structural

fire barrier would be. In addition, in most cases, a

seal failure would initially create a localized hot spot

in the adjacent fire area in the area of the seal. If

there are no combustible materials in the adjacent fire

area in the vicinity of the failed seal (for example, if

the penetration seal surrounds a pipe), smoke and hot

gases will migrate into the adjacent area, but the

spread of fire into the area will be limited. If there

are combustible materials in the vicinity of the failed

seal (for example, if the penetration seal surrounds a

loaded cable tray that passes from one fire area to

another), the fire could spread into the adjacent area

more readily. In this instance, a more detailed fire

hazards analysis is needed to assess the potentially

adverse effects of the fire spread. Regardless, such a

fire scenario is less threatening than the failure of a

structural fire barrier.

2 REVIEW OF REACTOR

OPERATING EXPERIENCE

2.1 Licensee Event Reports

In NUREG-1552, the staff reported that in 1994 the

licensee event report (LER) database maintained by

Oak Ridge National Laboratory contained about

58,000 LERs and that 318 (about 0.5 percent) of

them, involved fire barrier penetrations. (For this

discussion, "LERs" also includes LER supplements.)

In NUREG-1552 the staff documented the results of

its review of the LERs submitted between 1989 and

1993, inclusive. The staff found that licensees for

about 20 plant sites had submitted 141 LERs

regarding fire barrier penetration seals. In support of

the reassessment documented here, the staff obtained

the LERs regarding fire barrier penetration seals that

were submitted in 1987 and 1988, and 1994 through

September 1998, inclusive. The staff found that 9

plant sites submitted 16 LERs during 1987; 12 plant

sites submitted 19 LERs during 1988; and 14 plant

sites submitted 34 LERs between 1994 and

September 1998.

Overall, the staff found that the technical problems

with penetration seals that were reported between

1987 and September 1998, inclusive, could be

classified into four major categories. In descending

order of the number of reported occurrences, these

were

(1) seal not installed or breached (58 occurrences),

(2) seal not properly installed (63 occurrences),

(3) inadequate documentation (19 occurrences), and

(4) seal degraded or damaged (17 occurrences).

Appendix F shows the numbers of LERs regarding

fire barrier penetration seals that were submitted by

year from January 1987 through September 1998.

Appendix G details the types of problems (the four

major categories and subcategories) that were

reported by year for the same period, and the number

of times the problems occurred. Appendix H reports

on each LER that the staff considered during this

reassessment of penetration seals. (The total number

of LERs for 1989 through 1993 differs from the

number reported in NUREG-1552 because the staff

removed from consideration reports that were not

related to technical problems, e.g., missed

surveillances. Note also that some licensees do not

consider that penetration seal deficiencies are

conditions that put a plant outside its design basis

and, therefore, do not report such deficiencies in

LERs.)

As part of this reassessment, the staff reviewed the

LERs submitted during 1987 and 1988 and those

submitted from 1994 through September 1998. The

staff also reconsidered the LERs that were submitted

from 1989 through 1993. On the basis of its reviews,

the staff made the following observations:

(1) The types of problems that were reported

during 1987 and 1988 and from 1994 through

1998, were consistent with the types of

problems reported in the LERs submitted from

1989 through 1993. The staff did not uncover

new types of problems.

(2) It appears that the types of problems and

deficiencies that have been found (e.g., voids,

cracks, inadequate documentation) have

involved each type of seal used by industry

(e.g., grout, silicone foam, and silicone

elastomer).

3 NUREG-1552, Supp. 1
Review of Reactor Operating Experience

(3) Overall, the number of LERs submitted each

year has decreased from a high of 23 in 1989

to 8 in 1998 (through September).

(4) The number of occurrences of penetration seal

deficiencies has decreased from a high of 25

in 1989 to 7 in 1998 (through September).

(5) After its first comprehensive technical

assessment of fire barrier penetration seals, the

NRC staff issued Information Notices (INs)

88-04; 88-04, Supplement 1; and 88-56 to alert

industry to potential seal problems. In

response to these INs, there was significant

industry scrutiny of installed penetration seals

and penetration seal programs. On the basis of

its best-effort search of LERs and NRC

inspection reports (see Section 2.2, below), the

staff found that the licensees for at least 45

plants have conducted enhanced2 100-percent

penetration seal inspections in response to the

INs. (See Appendix J for a complete list of

references.)

(6) Most of the licensees that have conducted 100

percent seal inspection programs found seal

deficiencies. The findings ranged from

negligible to widespread problems involving

each of the four categories of problems. These

licensees strengthened their programs to

reduce the likelihood of recurrence.

(7) Many of the deficiencies concerning failure to

install seals, improper seal installation, and

inadequate documentation existed since the

plant was built. However, these types of

problems can occur at any time during the life

of the plant. For example, during plant

outages, temporary and permanent

modifications that involve routing cables are

commonplace. Such modifications require

breaching existing penetration seals or making

new penetrations. Plant procedures specify

that the breached seals be restored and that

new penetrations be sealed with properly

designed and tested penetration seal

2For purposes of this discussion, an enhanced

program is one that exceeds the requirements of the

licensee's routine surveillance program. For

example, the licensee may have compared test

documentation to installed seal configurations or

removed damming boards to verify the thickness of

the installed seals.

assemblies. Sometimes this is not done and

the discrepancies are not found until a

subsequent penetration seal surveillance.

(8) In some cases, licensees conservatively

reported such superficial problems as surface

imperfections and small cracks, splits, and

gaps, which would not have precluded the

seals from performing their intended fire

protection design function.

(9) Licensees appear to understand potential

problems with and corrective actions for fire

barrier penetration seals.

(10) Plant age does not appear to be a critical

attribute as to whether or not a plant is prone

to seal problems. Of the 45 plants known to

have completed 100-percent seal inspection

programs, about half operated before January

1, 1979 (and are covered by the regulations in

Appendix R), and half began operations later

and are not covered by the regulations in

Appendix R.

(11) Overall, the safety significance and risk

significance of the reported deficiencies were

low. The potential safety significance of the

reported problems is discussed in Section 3.

The risk significance is discussed in Section 4.

Of the LERs submitted since the staff issued

NUREG-1552, two indicated widespread plantspecific deficiencies. The first involved Washington

Nuclear Project 2 (WNP2) and the second involved

Maine Yankee. The staff was aware of the

deficiencies at WNP2 through previous NRC

inspections and it documented these deficiencies and

the licensee's corrective actions in Section 5.5.5 of

NUREG-1552. The staff's assessment of the Maine

Yankee report is in Section 6.6 of this report.

2.2 NRC Inspections

As part of this reassessment, the staff conducted a

best-effort search for NRC inspections of penetration

seal programs. The staff found that between 1988

and March 1998, it conducted 153 inspections that

involved installed penetration seals and penetration

seal programs at 87 plants. Of these, 42 (48 percent)

were Appendix R plants (operating prior to

January 1, 1979). The inspectors reviewed the

adequacy of penetration seal installations,

qualification, and surveillances. They also followed

up on issues reported in LERs and weaknesses noted

NUREG-1552, Supp. 1 4
Review of Reactor Operating Experience

during previous NRC inspections. In some cases, the

inspectors reviewed the 100-percent penetration seal

reevaluation programs performed by the licensees. In

other cases, the inspectors walked down the seal

installations to assess their adequacy. In general, the

inspectors found that the penetration seal programs

were comprehensive, timely, and acceptable. In

some cases, the inspectors found deficiencies and

issued notices of violations. Each of these

inspections is summarized in Appendix I.

On the basis of its review of the NRC inspection

findings, the staff made the following observations:

(1) The types of problems found during

inspections were consistent with the types of

problems reported in LERs. The staff did not

identify new types of problems during its

inspections.

(2) The inspection reports, like the LERs, revealed

that licensees occasionally find plant-specific

deficiencies.

(3) For the most part, the licensees maintained

satisfactory fire barrier penetration seal

programs.

(4) Licensees understand potential fire barrier

penetration seal problems, have the means to

correct problems, and have taken appropriate

and timely actions to correct penetration seal

deficiencies.

(5) The NRC inspection reports did not reveal

widespread or potentially generic problems of

safety significance.

As noted in NUREG-1552, the NRC's routine fire

protection inspection procedures are contained in the

NRC Inspection Manual in Inspection

Procedure 64704, "Fire Protection Program"

(March 18, 1994). This procedure directs the

inspectors to visually inspect the fire barriers

associated with two plant fire areas and ensure that

the electrical and mechanical penetration seals are

functional. However, the procedure did not give

specific guidance for inspecting the seals or

establishing their functionality. The lack of specific

inspection guidance was viewed as a potential

weakness in the NRC reactor fire protection program.

Therefore, the staff revised Procedure 64704 in

September 1997, to add guidance for inspecting

penetration seals as a part of its routine fire

protection inspections.

In NUREG- 1552, the staff also reported that it was

preparing the new fire protection functional

inspection (FPFI) program that it had described in

SECY-95-034, "Status of the Recommendations

Resulting from the Reassessment of the NRC Fire

Protection Program." Since it issued NUREG-1552,

the staff has drafted the FPFI procedures and

guidelines and has started the pilot FPFI program.

The FPFI procedures and guidance contain detailed

guidance for inspecting fire barrier penetration seals

and seal programs. These procedures and guidelines

are being used during the FPFIs and are available for

NRC inspectors and licensees to use on an as-needed

basis independent of an FPFI.

2.3 Fire Experience

The staff reviewed the fire event databases compiled

by Sandia National Laboratories, which contained

data from 1965 thorough 1985, and the Electric

Power Research Institute, which contained data from

1965 through 1988. The staff found no reports of

nuclear power plant fires that challenged the ability

of fire rated structural barriers or fire rated

penetration seals to confine a fire in accordance with

their fire protection design function. The staff also

reviewed the LER database discussed in Section 2.1,

which contains data from 1980 to the present, and

again, found no reports of nuclear power plant fires

that caused the failure of a fire rated structural barrier

or a fire rated penetration seal. In addition, since the

staff issued NUREG-1552, AEOD issued a special

study titled "Fire Events-Feedback of U.S.

Operating Experience" (June 1997), which covers

operating experience from 1965 through 1994. This

AEOD study does not contain fire events that

challenged either fire-rated structural barriers or firerated penetration seals.

It has been suggested that the March 22, 1975, fire at

the Browns Ferry Nuclear Plant propagated through a

fire-rated penetration seal and, therefore, there is

industry experience that a fire challenged such a seal.

The staff does not agree. As reported in

NUREG-0050, "Recommendations Related to

Browns Ferry Fire" (February 1976), "the seal that

caught fire differed from the [fire] seal as designed

and tested." For example, the installed seal in which

the fire started used flexible polyurethane foam rather

than the spray polyurethane foam specified in the

plant's original design criteria. In addition, the

installed seal did not have the fire-retardant coating

specified in the design criteria. Furthermore, the

report stated that "a properly made fire stop of the

5 NUREG-1552, Supp. 1
Safety Significance

Browns Ferry design (with Flammastic and without

flexible foam) would probably not have initiated the

fire" and "even if a fire had started, a fire stop made

in accordance with the original design may well have

prevented its spread outside of the room where it

started."

2.4 Summary of Operating

Experience

The LERs and NRC inspection reports show that

many plants have performed 100-percent penetration

seal inspections and corrective action programs since

1987. The staff found no evidence of generic

problems of safety significance with penetration seal

materials or safety-significant failures of penetration

seals. On the basis of its review, the staff concluded

that the licensees have been effective in finding

penetration seal deficiencies and have taken timely

and appropriate actions to correct identified

discrepancies. In view of the large number of

penetration seals installed in nuclear power plants,

the staff expects that plant-specific deficiencies may

occasionally be found during licensee surveillances

and NRC inspections. However, the LERs and NRC

inspection findings show that licensees understand

the potential fire barrier penetration seal problems

and that fire test results and qualified fire-resistant

seal materials and designs are available. Therefore,

licensees have the means to correct problems.

Appendix J lists plants that, on the basis of docketed

information, are known to have performed 100-

percent penetration seal inspection programs that

exceeded the specifications of the licensees' normal

fire barrier surveillance programs. Appendix K lists

the docketed references (LERs and NRC inspection

reports), by plant, that the staff considered in this

reassessment of fire barrier penetration seals.

3 SAFETY SIGNIFICANCE

3.1 Fire Protection Program

The basic fire protection regulation for commercial

nuclear power plants is Title 10 of the U.S. Code of

Federal Regulations, Part 50, Section 50.48, "Fire

protection." Section 50.48(a) states that each

operating nuclear power plant must have a fire

protection plan that satisfies General Design

Criterion (GDC) 3 of Appendix A to 10 CFR Part 50,

"Fire protection," and notes that fire protection

guidance for nuclear power plants is contained in

Branch Technical Position (BTP) Auxiliary Power

Conversion Systems Branch (APCSB) 9.5-1,

"Guidelines for Fire Protection for Nuclear Power

Plants;" and Appendix A to BTP APCSB 9.5-1,

"Guidelines for Fire Protection for Nuclear Power

Plants Docketed Prior to July 1, 1976." These two

NRC documents specify preferred methods for fire

protection program design. In addition,

Section 50.48(b) states that Appendix R to 10 CFR

Part 50, "Fire Protection Program for Nuclear Power

Facilities Operating Prior to January 1, 1979,"

establishes fire protection features required to satisfy

GDC 3 with respect to certain generic issues for

nuclear power plants licensed to operate before

January 1, 1979. Fire protection programs that meet

the criteria of either BTP APCSB 9.5-1 or Appendix

A to BTP APCSB 9.5-1 and the applicable sections

of Appendix R satisfy 10 CFR 50.48 and GDC 3.

NUREG-0800, "Standard Review Plan," (SRP)

Section 9.5-1, "Fire Protection Program,"

incorporates the guidance of BTP APCSB 9.5-1 and

Appendix A to BTP APCSB 9.5-1 and the criteria of

Appendix R. Therefore, fire protection programs

that meet the guidelines of SRP Section 9.5-1 also

satisfy 10 CFR 50.48 and GDC 3.

The objective of the fire protection program required

by 10 CFR 50.48 is to minimize both the probability

and consequences of fires. As discussed in

Section 1, the licensees use the concept of defense in

depth to achieve a high degree of fire safety. The

licensees determine the adequacy of fire protection

for plant safety systems and areas by analyzing the

effects of postulated fires. In general, the primary

means of fire protection consists of fire barriers and

fixed automatic fire detection and suppression

systems. In addition, manual fire fighting capability

is provided throughout the plant to limit the extent of

fire damage. The plant fire hazards analysis

addresses the following variables and attributes:

(1) the NRC fire protection requirements and

guidance that apply;

(2) amounts, types, configurations, and locations

of cable insulation and other combustible

materials;

(3) fire loading and calculated fire severities;

(4) in situ fire hazards;

(5) automatic fire detection and suppression

capability;

NUREG-1552, Supp. 1 6
Safety Significance

(6) layout and configurations of safety trains;

(7) reliance on and qualifications of fire barriers,

including fire test results, the quality of the

materials and system, and the quality of the

installation;

(8) fire area construction (walls, floor, ceiling,

dimensions, volume, ventilation, and

congestion);

(9) location and type of manual fire fighting

equipment and accessibility for manual fire

fighting;

(10) potential disabling effects of fire suppression

systems on shutdown capability;

(11) availability of oxygen to support combustion

(for example, inerted containment); and

(12) post-fire safe-shutdown capability, including

alternative or dedicated shutdown capability.

During its reviews and inspections of the licensees'

fire protection programs, the staff ensured that each

licensee had provided an adequate level of fire

protection.

3.2 Safety Significance Ranking of

Penetration Seal Deficiencies

In general, the potential safety significance of a

deficient fire barrier penetration seal depends on such

factors as the nature and extent of the deficiency; the

importance of the plant systems and components in

the fire area (and adjacent areas); the amounts, types,

configurations, and locations of any combustible

materials and fire hazards in the areas; the potential

for fire growth in the areas; the fire protection

features installed in the areas; and the accessibility of

the areas to the plant fire brigade. The actual safety

significance and the importance of a specific seal

depends on these factors and on such other factors as

its size, its location or position in the fire barrier, and

the number and sizes of the other seals in the barrier.

Appendix G summarizes the types of penetration seal

problems and deficiencies that were reported in

LERs, by year, from 1987 through September 1998,

inclusive. It is the staff's judgment that, in general,

the four categories of deficiencies presented in

Section 2.1 of this report and in Appendix G can be

ranked from highest potential safety significance to

lowest as follows: (1) seal not installed or breached,

(2) seal not properly installed, (3) seal degraded or

damaged, and (4) inadequate documentation.

3.3 Generic Assessment of Safety

Significance

For purposes of the following discussion, the safety

significance of a fire barrier penetration seal can be

thought of as being the role the seal plays in

preventing a fire from spreading from the fire area of

origin to an adjacent fire area. In the Federal

Register notice that issued the proposed Appendix R

to 10 CFR Part 50,1 the staff stated that the

"phenomenon of fire is believed to be sufficiently

well understood to permit evaluation of existing and

potential fire hazards and probable extent of damage

should a fire occur. Such evaluations are useful in

assessing the possible consequences of fire in a given

area." In this regard, a generic assessment is

instructive for understanding the safety significance

of fire barrier penetration seals.

As discussed in Section 1, licensees rely on a

defense-in-depth concept that incorporates several

fire safety measures. In sum, automatic fire detection

and suppression systems are provided in most areas

that have safe-shutdown equipment. Trained fire

brigades are required to be on duty 24 hours a day at

all plants. All areas that have safe-shutdown

equipment contain manual fire suppression features.

Fuels that can feed a fire and ignition sources to start

a fire are controlled. Taken together, these factors

represent an adequate means of fire protection at the

plants and ensure that operations can be conducted

without an undue risk to the health and safety of the

public. In general, every echelon of fire protection

defense in depth would have to either fail or be

significantly compromised for a fire to breach a fire

barrier penetration seal and adversely affect the safeshutdown capability or cause other operational

problems. Specifically, the following would have to

occur:

(1) Despite the plant fire prevention program, a

fire would have to occur.

(2) The fire would have to go undetected. That is,

3

U.S. NRC, "Fire Protection Program for Nuclear

Power Plants Operating Prior to January 1, 1979,"

Federal Register, Vol. 45, No. 105, May 29, 1980,

pp. 36082-36090.

7 NUREG-1552, Supp. 1
Safety Significance

the automatic fire detection and alarm system

would have to fail. In addition, plant

personnel would have to fail to discover the

fire.

(3) The fire would have to grow beyond the

incipient stage, spread, and become large.

This means that the fire area would have to

contain transient and in situ combustible

materials of sufficient types, amounts, and

configurations to support fire growth and

spread.

(4) The automatic fire suppression system (if there

is one) would not operate and control the fire,

or if it operated, it would fail to control the

fire.

(5) Manual fire suppression activities would not

be employed to control and suppress the fire.

(6) The fire must expose the safe-shutdown

components located in the originating fire area

and cause fire damage that renders the

components nonfunctional. For this to

happen, the fire must either start near the

components or it must spread close enough to

the components so that the components are

damaged by direct flame impingement or

radiative heat transfer. Alternately, the fire's

products must adversely affect the

safe-shutdown components located in the fire

area. For example, hot gases from the fire

would rise to the ceiling and form a hot gas

layer. Safe-shutdown components (e.g.,

cables) located near the ceiling and within the

hot gas layer could be damaged by the

convected heat even if they are located away

from the burning area.

(7) The fire must also spread to a penetration seal

installed in a structural fire barrier that

separates the fire area of origin from an

adjacent fire area with the other train of

redundant safe-shutdown components.

(8) The uncontrolled fire must burn through the

fire-resistant penetration seal assembly (which

in some cases, could take more than 3 hours).

(9) After the fire bums through the penetration

seal, it must continue to burn and spread from

the penetration to the redundant safe-shutdown

components located in the adjacent fire area,

where it must cause sufficient fire damage to

the components to affect their ability to

function. That is, the scenario described under

items I through 6 would also have to occur in

the second fire area.

As discussed in Section 1, fire barrier penetration

seals are passive fire protection features that

accomplish their intended fire protection function by

their very presence. Penetration seals are important

features because they help confine a fire to its area of

origin. There can be no question that when properly

designed and installed, the various types of

penetration seals currently installed in nuclear power

plants will provide fire resistance equivalent to the

barriers in which they are installed and will perform

their intended fire protection function by confining a

fire to the area of origin. The types of penetration

seal deficiencies described in Section 2 and in

Appendix G can reduce the fire-resistance

capabilities of penetration seals. Nevertheless, it is

the staff's opinion that, in general, the relative safety

significance of such deficiencies is low for the

following reasons: in most cases, the deficiencies

may reduce the fire resistance of the seal, but they do

not render it useless; the defense-in-depth concept

ensures that multiple safety measures are

incorporated; automatic fire detection and

suppression systems are provided in areas that have

safe-shutdown systems and components; trained fire

brigades are required to be on duty 24 hours a day at

all plants; and transient and in situ fuels and fire

hazards that can feed a fire, and ignition sources that

can start a fire, are controlled. Therefore, it is

unlikely that a fire significant enough to challenge a

fire barrier penetration seal will occur. How these

factors affect the various types of penetration seal

deficiencies is discussed in Sections 3.3.1 and 3.3.2,

below.

3.3.1 Improperly Installed or Degraded

Seals and Inadequate

Documentation

As discussed in Section 1, the fire endurance tests

maximize fire severity by subjecting the penetration

seal to a fire of rapidly rising temperature in a

relatively small and confined space. In the event of

an actual fire at a nuclear power plant, the fire

resistance required of a penetration seal depends on

the expected severity of the fire to which it may be

exposed. With few exceptions, nuclear plant fire

loads are not great enough to produce a fire

approaching the severity of a test fire (time and

temperature). It is expected that the temperature of

NUREG-1552, Supp. 1 8
Safety Significance

most actual fires at nuclear power plants would rise

slower than the temperature of the standard test fire.

Most plant areas have controls on ignition sources;

these controls help reduce the occurrences of fires.

Most plant areas are equipped with other passive and

active fire protection features, and many are

continuously or regularly occupied by plant

operators, security staff, and other personnel, all of

whom contribute to early fire detection and

suppression activities. For example, plant fire

detection systems give reasonable assurance that a

fire will be detected in its incipient stage and before

there is any significant propagation of flame; or rise

in temperature. The detection system would send an

alarm to the continuously manned control room, and

the control room operators would dispatch the plant

fire brigade. The fire brigade would then extinguish

the fire.

In a plant area that is protected by an automatic fire

suppression system, should the fire develop beyond

the incipient stage before the fire brigade responds,

the system would actuate and either control or

extinguish the fire. Therefore, there is reasonable

assurance that a fire will not challenge a fire barrier

penetration seal.

In addition, in large open spaces, such as exist in

many nuclear plant fire areas, a fully developed fire

may occur in one part of the area (e.g., in

concentrations of cables), but it is not probable that

the entire volume (fire area) would be engulfed in

flames (flashover) before an automatic fire

suppression system actuated or manual fire

suppression activities were employed. Unless a fire

reaches the fully developed stage, it is not likely to

present a credible challenge to any nuclear power

plant penetration seal. Moreover, even in cases in

which the fire barrier penetration seals are degraded

or deficient, they will offer some measure of fire

protection. Some of the reported deficiencies could

have reduced the fire-resistance rating of seals under

test conditions and the fire protection effectiveness of

in-plant seals (e.g., inadequate seal thickness).

However, other deficiencies (splits, shrinkage,

inadequate documentation) may have little or no

effect on seal performance.

3.3.2 Unsealed and Breached Penetrations

For the cases discussed in Section 3.3.1, the installed

penetration seals are degraded or deficient, but will

provide some measure of fire protection. Intuitively,

conditions involving missing and breached seals

involve potentially higher safety significance,

because this measure of protection is missing

altogether and the fire may have a direct path to

spread from one fire area to another.

It is important to note that there is no regulatory

requirement that fire-rated seals be installed in all

penetrations through fire barriers that form fire area

boundaries or that seals have either (1) the same fireresistance rating as the structural fire barrier in which

they are installed or (2) a 3-hour fire resistance

rating. In Generic Letter (GL) 86-10, "Implementation of Fire Protection Requirements"

(April 24, 1986), the staff presented guidance for

satisfying NRC regulatory requirements for fire

protection. In Enclosure 1 to GL 86-10, the staff

interpreted Appendix R requirements.

Interpretation 4, "Fire Area Boundaries," stated, in

part,

The term "fire area" as used in Appendix R

means an area sufficiently bounded to

withstand the [fire] hazards associated with

the area and, as necessary, to protect

important equipment within the area from a

fire outside the area. In order to meet the

regulation, fire area boundaries need not be

completely sealed floor-to-ceiling, wall-towall boundaries. However, all unsealed

openings should be identified and considered

[in] evaluating the effectiveness of the overall

barrier. Where fire area boundaries are not

wall-to-wall, floor-to-ceiling boundaries with

all penetrations sealed to the fire rating

required of the boundaries, licensees must

perform an evaluation to assess the adequacy

of fire boundaries in their plants to determine

if the boundaries will withstand all [fire]

hazards associated with the area.

This regulatory position established that certain

penetration seals need not have the same fire rating

as the barrier in which they are installed and, indeed,

that certain fire barrier penetrations may not need to

be sealed at all. Licensees evaluate such seals on a

case-by-case basis. The engineering evaluations

performed to assess the effectiveness of the

penetration seals are based on the expected fireresistive performance of the seal and on the fire

hazards and fire protection features in the fire area.

Nevertheless, on the basis of its experience, the staff

believes that most licensees install 3-hour fire-rated

penetration seals in fire area boundaries.

9 NUREG-1552, Supp. 1
Safety Significance

It should be noted that with up to 10,000 fire barrier

penetration seals per nuclear unit, the instances of

unsealed penetrations and breached penetration seals

that have been reported are rare. Open penetrations

are more safety significant than degraded penetration

seals. However, even in cases of missing or breached

seals, most of the considerations discussed in

Section 3.3.1 still apply. That is, the defense-indepth concept ensures that multiple safety measures

are incorporated; automatic fire detection and

suppression systems are provided in areas that have

safe-shutdown systems and components; trained fire

brigades are required to be on duty 24 hours a day at

all plants; and transient and in situ fuels and fire

hazards that can feed a fire and ignition sources that

can start a fire are controlled. To spread through an

open penetration, the fire would have to be large and

uncontrolled. In this case, a localized hot spot would

occur in the adjacent fire area in the area of the seal.

If there are no combustible materials in the adjacent

fire area in the vicinity of the open penetration (for

example, if the penetration seal encloses a pipe),

smoke and hot gases will move into the adjacent area,

but the spread of fire into the area would be limited.

Conversely, if there are combustible materials in the

vicinity of the failed seal (for example, if the

penetration seal encloses a loaded cable tray that

passes from one fire area to another), the fire could

spread into the adjacent area more readily. However,

in the event a fire spreads through an unsealed

penetration, the fire threat to the adjoining fire area

should be readily mitigated by the plant fire brigade.

As an example, consider the following. On

March 22, 1975, the Browns Ferry Nuclear Power

Plant had the worst fire ever to occur in a commercial

nuclear power plant operating in the United States.

As reported in NUREG-0050, the fire spread along

cable trays from the cable spreading room, through a

cable penetration, and into the reactor building. The

fire burned cables in cable trays for almost 7 hours.

During that time, portable extinguishers were used

intermittently to no effect. After almost 7 hours, the

decision was made to fight the fire with water. Two

men using a fire hose extinguished the fire within 15

minutes. This experience demonstrated that a

significant and challenging nuclear power plant fire

could be readily extinguished if appropriate and

timely fire fighting efforts are employed. Since the

fire at Browns Ferry, licensees have made significant

improvements in fire brigade training and fire

fighting capabilities. The staff believes that if timely

and appropriate action is initiated, a fire at an open

penetration will not create any significant problems.

Therefore, on the aforementioned bases, although the

staff considers an open penetration to be more

significant than a degraded seal, it believes that the

relative safety significance of missing and breached

seals, although potentially higher than the other

common types of seal deficiencies, is low.

3.4 Seal-Specific Assessment of

Safety Significance

For the reasons discussed above, in general, the

safety significance of deficient fire barrier

penetration seals is low. However, the actual safety

significance of specific deficiencies in fire barrier

penetration seals depends on many factors and

variables. These include the importance of the plant

systems and components in the fire area (and

adjacent areas); the types, amounts, configurations,

and locations of any combustible materials and fire

hazards in the areas; the potential for fire growth in

the areas; the fire protection features installed in the

areas; the accessibility of the areas to the plant fire

brigade; the type, size, and location of the penetration

seal; the nature and extent of the seal deficiencies;

and the overall effectiveness of the defense-in-depth

process.

Clearly, certain fire areas present a more credible

challenge to deficient fire barrier penetration seals

than others. For example, it is likely that a fire

involving a turbine generator lubricating oil system

would present a significant fire exposure to the fire

barrier penetration seals installed in the fire wall that

separates the turbine building from the auxiliary

building. If the seals are properly designed and

installed and the other components of the fire

protection program (e.g., fire brigade) are effective,

they are likely to withstand the challenge and prevent

the fire from spreading from the turbine building into

the auxiliary building. However, if the seals are

deficient, it is conceivable that they could fail under

the fire exposure and allow the fireto spread into the

auxiliary building. Again, the actual adverse

consequences of this situation would depend on such

factors as the location of the burnthrough into the

auxiliary building and the location of combustibles

and important plant equipment in the vicinity of the

burnthrough. The significance of such a scenario

could be compounded by the fact that the fire wall in

the turbine building could be common to several

auxiliary building fire areas. Therefore, if the

penetration seals were to fail, a single fire could

adversely impact several plant components and

systems.

NUREG-1552, Supp. I 10
Plant-Specific Experience

On the other hand, a fire involving a charging pump

motor is not likely to present nearly as significant a

challenge to fire barrier penetrations installed in the

pump cubicle walls. In this case, even if the seals are

deficient, the fire is not likely to have an adverse

effect on plant safety systems located outside of the

pump cubicle.

4 RISK SIGNIFICANCE

The calculated core-damage frequency (CDF) from

fires, and the contribution of fire risk to a plant's total

CDF, is a plant-specific determination that is

dependent on the plant configuration and the

methodology and assumptions that are used for the

analysis. The application of the calculated CDF to

assess the fire risk of one plant against the fire risk at

another plant is inappropriate.

The postulated fire scenarios that are the major

contributors to core damage for most plants are those

in which the redundant divisions of post-fire safeshutdown components and systems are located in the

same fire area. In these scenarios, fire barrier

penetration seals are not considered (not modeled) in

the assessment, because the factors mentioned earlier

have a greater effect on CDF.

Scenarios involving the spread of fire from one plant

fire area to another and evolving to core damage are

of low frequency. This is a result of several defensein-depth measures, such as administrative controls on

combustible materials and "hot" work, automatic fire

detection, automatic fire suppression, and

intervention by the plant fire brigade. On the basis of

its reviews of fire risk assessments completed thus

far, penetration seals have not been relied upon for

the prevention of core damage. It is the staffs

judgment that failure of a plant's barrier penetration

seals would not significantly alter the overall

contribution of fire risk to the plant's total calculated

CDF.

5 COMPENSATORY MEASURES

The use of fire watches in instances of degraded or

inoperable fire barriers is an integral part of NRCapproved fire protection programs. In general, these

approved compensatory measures specify the

establishment of a continuous "fire watch" or an

hourly fire watch patrol where automatic detection

systems protect the affected components. Fire

watches are personnel trained by the licensees to

inspect for the control of ignition sources, fire

hazards, and combustible materials; to look for signs

of incipient fires; to provide prompt notification of

fire hazards and fires; and, in some cases, to take

appropriate actions to begin fire suppression

activities. Generally, therefore, by providing

additional fire prevention activities through enhanced

capabilities to find fire hazards and, in the case of a

fire, through augmented suppression activities before

a penetration seal's ability to endure a fire is

challenged, fire watches compensate for degraded

fire barrier penetration seals. The licensees that

reported fire barrier penetration seal deficiencies

established fire watches in accordance with their

technical specifications or license conditions as a

compensatory measure.

6 PLANT-SPECIFIC

EXPERIENCE WITH FIRE

BARRIER PENETRATION

SEALS

The staff reviewed in detail the status of penetration

seal programs at several plants that have undertaken

major penetration seal corrective action programs.

6.1 Vermont Yankee Nuclear

Power Station

On March 19, 1992, during an inspection of fire

barrier penetration seals at Vermont Yankee Nuclear

Power Station, the licensee found a penetration

containing unapproved material. The next day,

another penetration seal was found to be degraded.

The licensee took compensatory measures and began

an investigation into the cause of the degradation.

Later, while implementing corrective actions in

December 1992, the licensee found more problems.

It performed additional seal inspections and found

that the seal discrepancies were more widespread

than was originally believed. On January 15, 1993,

the licensee issued Licensee Event Report

(LER) 93-001. The licensee declared 57 penetration

seals inoperable and established a task force to

inspect all fire barrier penetration seals. Ultimately,

the licensee repaired more than 900 (64 percent) of

the 1400 fire barrier penetrations installed at

Vermont Yankee and upgraded almost 300

penetrations (21 percent). The licensee attributed

most of the as-found unacceptable penetrations to

inadequate design or to inadequate installations made

by a contractor between 1979 and 1980. (That

I1I NUREG-1552, Supp. I
Plant-Specific Experience

contractor is no longer in business.) The licensee

attributed the failure to identify these issues to

inadequate surveillance procedures. The licensee

completed the repairs to affected barriers and the

required surveillances in May 1993. In subsequent

years (1994-1997), routine fire barrier surveillances

discovered five degraded penetration seals. These

events were described in LERs 94-018, 94-018-01,

95-004, 96-026, and 96-026-01. In 1998, the

licensee reported seal problems in LERs 98-001,

98-001-01, 98-008, 98-008-01, 98-014, and

98-014-01. These LERs reported problems with 4

penetration seals. These problems were resolved by

the licensee.

6.2 Wolf Creek Nuclear

Generating Station

6.2.1 Operating Experience

In December 1984, the licensee for Wolf Creek

Nuclear Generating Station (WCNGS) issued a

nonconformance report because, 22 penetration seals

lacked document traceability. The licensee

completed corrective actions in 1985. Later, in early

1987, B&B Promatec Corporation (Promatec),

Houston, Texas, the penetration seal installation

contractor, notified the NRC that of 40 seals

inspected, the silicone foam material in 20 showed

voids and shrinkage. The problems had involved

installation methodology, inadequate quality control

(QC) methods, and rapid, chemically induced,

expansion of the silicone foam material. The

licensee issued LER 87-010 on February 6, 1987.

This problem affected several other nuclear plants.

Promatec informed the industry of the problems and

submitted a Part 21 notification. The NRC issued

IN 88-56 to advise licensees of the problems

discovered at Wolf Creek.

In 1987, the licensee established a task force to

develop a corrective action plan. The inspection plan

covered the removal of damming boards and

inspection of accessible foam penetrations. The

scope of the program included inspections of more

than 1700 silicone foam penetration seals. As a

result of the inspections, the licensee repaired more

than 600 seals during 1987. Since 1987, the licensee

has found only minor problems during routine

inspections, and the licensee addressed these

promptly.

6.2.2 01 Investigation

In September 1988, the NRC Office of Investigations

(01) in Region IV initiated an investigation to

determine if company officials at Promatec or

WCNGS knowingly and intentionally failed to notify

the NRC in 1984 and 1985 about the defective seals.

In May 1987, Promatec had submitted a 10 CFR Part

21 report to the NRC, which stated that some silicone

foam fire barrier penetration seals installed by

Promatec at WCNGS did not meet minimum

specifications. During replacement of damaged fireresistant boards, WCNGS personnel found voids,

shrinkage, and lack of fill in approximately 25

percent of the seals.

The 01 investigation revealed that both Promatec and

Kansas Gas & Electric (KG&E) became aware in

1983 of a similar problem with silicone seals at

Callaway Nuclear Power Plant, also installed by

Promatec. However, a different method of

installation, a two-stage damming process, was

utilized at WCNGS. Following the discovery of the

problem at Callaway, Promatec conducted two seal

reinspections at WCNGS. KG&E rejected the results

of the first of these as too limited and indicative of a

potential problem similar to the problem encountered

at Callaway. The scope of the reinspection was

expanded; the second reinspection led Promatec to

conclude that there was a less than 2-percent

rejection rate of these seals from shrinkage and

voids. KG&E accepted the results of this

reinspection and concluded that the problem at

WCNGS was minor and not indicative of the

problem found at Callaway.

On the basis of its investigation, 01 concluded that

the problem with the seals at WCNGS was generic,

inherent both in the material and in the cable tie

inspection method utilized at the time the seals were

installed. 01 concluded that the silicone material

shrinks and expands depending on temperature

changes and that it is difficult to install seals so as to

ensure a complete fill, even utilizing the stage

damming method of installation. 01 also concluded

that the inspection method used at WCNGS was

inaccurate and could not reveal all voids, gaps, or

missing fill in the seals.

From the time the seals were first installed, KG&E

was aware of the seal inspection method used by

Promatec. This was the acceptable method of

inspection used by all sealing contractors at the time.

Although KG&E knew about Callaway's problems,

NUREG-1552, Supp. I 12
Plant-Specific Experience

and was questioned by an American Nuclear Insurers

(ANI) inspector and by the NRC regarding the

adequacy of the inspection method, it took no steps

to change to a visual inspection of the seals.

01 concluded that its investigation did not find

evidence that KG&E or Promatec personnel were

aware of specific problems at WCNGS and willfully

failed to notify the NRC, as required by

10 CFR 50.55(e). 01 also concluded that there is a

potential for similar problems at any nuclear plant

that utilized silicone foam seals and the method of

inspection used at WCNGS, regardless of who

installed the seals.

6.3 Salem Nuclear Generating

Station

Fire barrier penetration seals have been inspected at

least three times at the Salem Nuclear Generating

Station. NRC Inspection 93-80 was an Appendix R

inspection in which the licensee's penetration seal

inspection program was evaluated. The inspection

procedure was reviewed and the latest surveillance

report was reviewed. The licensee inspects 10

percent of the fire barrier penetration seals every 18

months. If one failure is found, then an additional

10-percent sample is inspected until no more failures

are identified. No failures were noted in the

surveillance that was reviewed. The inspectors also

reviewed the licensee's response to IN 88-56. The

licensee's silicone foam seals were installed without

the use of damming boards, making it very easy to

detect voids or gaps.

Penetration seals were inspected again as a restart

issue for Salem Inspection Report 96-10. The

licensee had completed a 100-percent inspection and

evaluation of all fire-rated penetration seals in 1992.

The inspectors reviewed the design analyses of

various types of penetrations and verified that the

licensee's penetration seal details were representative

of the tested seals, and that seals were bounded by

acceptable fire endurance tests. The inspector

concluded that the quality and configuration of

penetration seals were acceptable.

The NRC recently inspected Salem's corrective

actions to satisfy 10 CFR Part 50, Appendix R,

Sections III.G, and III.L (Inspection Report 97-09).

The inspectors compared "as built" penetration seals

to the fire endurance test configurations to verify that

as-built configurations were qualified by appropriate

fire endurance tests. The inspectors opened an

inspection followup item (IFI) for as-built drawings,

which did not identify important parameters with

respect to cable fill and its thermal mass, and the

maximum free area of unsupported penetration seal

installed within the penetration.

Overall, the inspectors concluded that test specimens

of the seals adequately represented and supported

qualification of the as-built seal designs that were

reviewed. The inspectors also concluded that the

licensee's engineering analysis methods were

adequate.

The licensee's staff has not identified any significant

problems at Salem regarding penetration seals.

6.4 Millstone Nuclear Power

Station

In LERs 93-006, 93-006-01, and 94-035, Millstone

Nuclear Power Station reported penetration seal

discrepancies. These LERs addressed unsealed

penetrations found by the licensee. The staff

reviewed LER 93-006 in NRC Inspection Report

93-19. The inspector reviewed the licensee's actions

in response to the discovery of the missing seals, and

reviewed the surveillance procedure that the licensee

uses to inspect seals. The inspector noted that the

procedure was adequate to enable proper inspection

of the seals. The inspector noted that Unit 1 had

identified only six other missing seals since 1990

through the seal surveillance program. This indicates

that unsealed penetrations do not seem to be a

programmatic concern at Millstone.

6.5 Maine Yankee Atomic Power

Plant

6.5.1 NRC Inspection

From June 26-30, 1995, NRC Region I staff

conducted a fire protection inspection at Maine

Yankee Atomic Power Plant. The inspection is

documented in NRC Inspection Report

50-309/95-15, which was transmitted to Maine

Yankee Atomic Power Company (the licensee for the

Maine Yankee plant) by letter dated

September 20, 1995.

The inspector reviewed the fire barrier program to

verify the adequacy of penetration seal installation,

qualification, and inspection activities. This review

13 NUREG-1552, Supp. 1
Plant-Specific Experience

also assessed the appropriateness of acceptance

criteria established for penetration seals to validate

operability and degradation that could prevent fire

barriers from providing effective separation during a

fire. The inspector concluded that the licensee's

procedures for seal inspections, and the training

program for seal inspectors, were good for

maintaining proper seal configuration and for early

detection of degraded conditions. These actions were

found to provide a defense against the propagation of

fire to adjacent plant areas.

The inspector reported that Maine Yankee relied on

Insulation Consultants & Management Services,

Incorporated (ICMS), to install the original

penetration seals. The licensee informed the

inspector that it had reviewed its purchase order

information and project files and found that it did not

apply any in-house quality control review for the

ICMS fire barrier installation work. The licensee

could not find the qualification and test reports

completed by ICMS to support the seal installations,

including fire and pressure test reports and

qualification of seal installers. Therefore, the

inspector could not verify the qualification of the

penetration seals installed at Maine Yankee.

The inspector opened an unresolved item regarding

the acceptability of penetration seal qualification,

testing, and installer qualifications.

6.5.2 Licensee Event Reports

After the NRC staff fire protection inspection, the

licensee conducted a scoping study in preparation for

fire barrier penetration seal walkdowns. By letter

dated July 29, 1996, the licensee submitted

LER 96-017, "Fire Barrier Penetration Seal

Discrepancy." The licensee reported that, during the

scoping study, it found fire barrier wall penetration

seals that did not have damming material in the

proper location. On the basis of these findings, the

licensee examined its criteria for penetration seals

and conducted a technical review of its penetration

seal design parameters. The licensee found

discrepancies between available test reports and

procedural guidance, and the in-plant penetration seal

configurations. In response to the discrepancies, the

licensee implemented compensatory fire watches and

developed a corrective action program. The planned

corrective actions were (1) determining why the

discrepancies were not found during previous

reviews; (2) evaluating the adequacy of procedures,

test reports, acceptance criteria, and field inspections;

(3) evaluating the adequacy of existing seal

configurations; and (4) inspecting all fire barrier

penetration seals.

By letter dated August 28, 1996, the licensee

submitted Revision 1 to LER 96-017. The licensee

reported that it had found three additional types of

deficiencies: (1) inadequate thickness of silicone

foam, (2) temporary seals that were not upgraded to

permanent seals for an indeterminate period, and

(3) one seal for which the expected pipe movement

exceeded the design rating of the seal.

6.5.3 Staff Followup

During a telephone conference on May 14, 1997,

Office of Nuclear Reactor Regulation (NRR) and

Region I staff obtained detailed information from the

licensee regarding the seal problems found and the

corrective actions. In addition, during the week of

May 12, 1997, NRR staff reviewed and observed the

problems found at Maine Yankee and the licensee's

corrective actions.

The penetration seals at Maine Yankee were installed

around 1978. Most of the original seals used silicone

foam. Since the original installation, the licensee has

visually inspected all the seals at each refueling

outage.

During the inspections and walkdowns that were

documented in LER 96-017-01, the licensee found

that more than a thousand seals required further

evaluation (including destructive examination); about

a thousand other seals had defects; and a small

number of seals had no defects. The licensee found

seals with inadequate thickness (the predominant

problem), foreign materials in seals, no damming

material, and the wrong seal material installed.

Although the licensee's design criteria specified a

minimum seal thickness of 7 inches, the average seal

thickness was 5 to 6 inches, and some seals were

only 2 to 3 inches thick. Although the licensee once

planned to repair and replace the seals with silicone

foam and silicone elastomer, the licensee has since

certified permanent cessation of power operation and

is now proceeding to decommission the facility.

The licensee informed the staff that it believes that

the installation deficiencies occurred because the

quality assurance and quality control procedures used

by the installation contractor during original seal

installation were inadequate. The licensee also

informed the staff that it believes it took so long to

NUREG-1552, Supp. 1 14
Review of Licensing Bases

discover the deficiencies because its inspection and

surveillance procedures did not cover all important

penetration seal attributes (e.g., the presence of

damming material was not a critical attribute) and

because training was insufficient. The licensee has

completed a major rewrite of its procedures.

The staff issued Information Notice (IN) 97-70,

"Potential Problems With Fire Barrier Penetration

Seals," on September 19, 1997, to tell industry of the

problems found at Maine Yankee. As mentioned

above, the licensee has since decided to shut the plant

down permanently.

6.5.4 Conclusions on Maine Yankee

Operating Experience

In NUREG-1552, "Fire Barrier Penetration Seals in

Nuclear Power Plants" (July 1996), the staff stated

that even though the overall condition of penetration

seal programs in industry is satisfactory, it expects

that plant-specific deficiencies may be found during

future licensee surveillances and NRC inspections.

Furthermore, the staff noted that licensees understand

potential fire barrier penetration seal problems;

industry consensus fire test standards are available

and licensees adhere to them; and fire test results and

qualified fire-resistant seal materials and designs are

available. On these bases, the staff concluded that

licensees have the means to correct problems, and

staff oversight will continue to ensure corrections on

a case-by-case basis. The penetration seal problems

found by the NRC inspector at Maine Yankee and

later reported by the licensee are consistent with the

known types of problems, as previously documented

by the staff in NUREG-1552. The reported problems

do not indicate new trends.

6.6 Conclusions

LERs, NRC inspections, and plant-specific corrective

action programs summarized above show that

licensees knew and understood the fire-resistive

capabilities of the penetration seal materials and

configurations; potential penetration seal testing,

design, installation, inspection, and maintenance

problems; and possible remedies and corrective

actions. These findings also indicate that the actions

taken by the staff in 1988 and 1994 had increased

industry awareness of possible penetration seal

problems, leading industry to more comprehensive

surveillance activities, maintenance practices, and

corrective actions. To provide added assurance that

penetration seal deficiencies will be found, the staff

revised the NRC fire protection core inspection

module to provide specific inspection guidance to

NRC inspectors.

7 REVIEW OF PLANTSPECIFIC LICENSING

BASES RELATED TO

SECTION III.M OF

APPENDIX R TO 10 CFR

PART 50

7.1 Introduction

The following supplements information presented in

Section 4 of NUREG-1552. On November 19, 1980,

the U.S. Nuclear Regulatory Commission (NRC)

published Appendix R, "Fire Protection Program for

Nuclear Power Facilities Operating Prior to

January 1, 1979," to Title 10 of the Code of Federal

Regulations (10 CFR) Part 50, and a revised Section

50.48, "Fire protection," in the Federal Register.

The revised Section 50.48 and Appendix R became

effective on February 17, 1981. It is important to

note that Appendix R is not a set of generically

applicable fire protection requirements and that it

applies only to plants that were operating before

January 1, 1979.

Section III of Appendix R contains 15 subsections,

lettered A through 0, which specify requirements for

nuclear power plant fire protection features. These

requirements are divided into two categories. The

first consists of those requirements that were backfit

to facilities operating before January 1, 1979,

regardless of whether or not the staff had previously

approved alternatives to the requirements of those

sections. These requirements are found in

Section HI.G, "Fire protection of safe shutdown

capability"; Section III.J, "Emergency lighting"; and

Section HI.O, "Oil collection systems for reactor

coolant pumps." The second category consists of

requirements that were backfit on a plant-specific

basis to the extent needed to resolve the "open" items

of previous NRC staff fire protection reviews. An

open item was defined as a fire protection feature

that had not been previously approved by the NRC

staff as satisfying the guidelines of Appendix A to

Branch Technical Position (BTP) APCSB 9.5-1, as

documented in a staff safety evaluation report

(SER). Section III.M, "Fire barrier cable penetration

15 NUREG-1552, Supp. 1
Conclusions

seal qualification," of Appendix R was one such

provision.

Section III.M states that penetration seal designs

shall utilize only noncombustible materials4 and shall

be qualified by tests that are comparable to tests used

to rate fire barriers. Section III.M contains the

following acceptance criteria:

(1) Cable fire barrier penetration seal has withstood

the fire endurance test without passage of flame

or ignition of cables on the unexposed side.

(2) Temperatures recorded on the unexposed side

are analyzed and the maximum temperature is

sufficiently below the ignition temperature of the

cable insulation.

(3) The fire barrier penetration seal remains intact

and does not allow a projection of water beyond

the unexposed surface during the hose stream

test.

After it published Appendix R in the Federal

Register, the staff sent letters to the licensees it

applied to summarizing the open fire protection items

and told each licensee which Appendix R

requirements it had to comply with to resolve the

items. Before the staff published NUREG- 1552,

Brookhaven National Laboratory (BNL), the staff s

technical assistance contractor, reviewed these letters

and found that 13 units had open items regarding fire

barrier penetrations when Appendix R was

published. They were:

15 units. If the plants used silicone-based fire barrier

penetration seal materials, which are classified as

"combustible" when tested in accordance with

ASTM Standard E- 136,' the staff reviewed how the

regulatory requirement of Section III.M of

Appendix R that penetration seals utilize only

noncombustible materials was addressed by the

licensees. The findings of these reviews are

documented below.

7.2 Plant-Specific Licensing Bases

7.2.1 Calvert Cliffs Nuclear Power Plant,

Units 1 and 2

By letter dated November 24, 1980, the staff

informed Baltimore Gas & Electric Company, the

licensee for the Calvert Cliffs Nuclear Power Plant,

Units I and 2, that the issue of ventilation and duct

fire dampers was an open item. The issue of fire

barrier penetration seals was not an open item.

Therefore, Section III.M of Appendix R does not

apply to the fire barrier penetration seals installed at

Calvert Cliffs.

7.2.2 Duane Arnold Energy Center

Silicone-based penetration seal materials are installed

in the plant.

In a letter of April 1, 1980, Iowa Light and Power

Company, the licensee for the Duane Arnold Energy

Center, stated that the penetration fire stops were

conservatively designed and provided an adequate

margin of safety for the plant fire protection design.

In a letter of November 24, 1980, the staff informed

the licensee that the tests described in its letter of

April 1, 1980, did "not substantiate the fire resistance

of the penetration seals installed at the plant." The

staff also stated that "[tlo meet the requirements of

Section III.M of Appendix R to 10 CFR Part 50, the

licensee should provide additional documentation to

verify that the seals which were tested and passed

were representative of those actually installed."

The licensee responded in a letter of February 4,

1981, in which it compared the fire barrier

penetration seal configurations it tested to those

installed in the plant, and claimed that the

Calvert Cliffs 1/2

Point Beach /2

Peach Bottom 2/3

FitzPatrick

Surry 1/2

Maine Yankee

Duane Arnold

Robinson 2

Pilgrim 1

On the basis of BNL's review, the staff reported in

NUREG-1552 that Section III.M of Appendix R

applied to 13 nuclear power plants. In support of the

review documented here, the staff again reviewed the

licensing basis for the Appendix R plants and added

Monticello and Vermont Yankee to the list of plants

that may be required to comply with Section III.M of

Appendix R. The staff then conducted a detailed

review of the fire protection licensing bases for these

4

A technical assessment regarding the combustibility

of silicone-based seal materials is presented in

Section 5.8 of NUREG-1552.

5 "Behavior of Materials in a Vertical Tube Furnace

at 750 'C," a pass/fail combustibility test method

accepted by the NRC.

NUREG-1552, Supp. 1 16
Review of Licensing Bases

information provided in previous correspondence

was sufficient to close the open item regarding fire

barrier penetration seals.

7.2.3 James A. FitzPatrick Nuclear Power

Plant

Silicone-based penetration seal materials are installed

in the plant.

In a letter of February 13, 1981, the staff transmitted

to the Power Authority of the State of New York, the

licensee for James A. FitzPatrick Nuclear Power

Plant (FitzPatrick), a supplemental SER in which it

concluded that the silicone elastomer penetration

seals installed at FitzPatrick met the criteria of

Section III.M of Appendix R and were, therefore,

acceptable. The open item regarding fire barrier

penetration seals at FitzPatrick was closed before the

effective date of Appendix R. Therefore,

Section HI.M of Appendix R does not apply to

FitzPatrick.

7.2.4 Maine Yankee Atomic Power Plant

Silicone-based penetration seal materials are installed

in the plant.

In Section 6.5 of this report, the staff discusses

Maine Yankee. The plant has been permanently shut

down and is being decommissioned.

7.2.5 Monticello Nuclear Generating

Plant

In a letter of November 24, 1980, the staff informed

Northern States Power Company, the licensee for

Monticello Nuclear Generating Plant, that the cable

tray penetrations at the south wall of the pipe and

cable tray penetration area do not have adequate fire

stops or adequate penetration seals. An NRC review

determined that the vertical cable trays that penetrate

the fire barrier are not sealed to provide adequate 3-

hour fire resistance. Therefore, in order to comply

with Section III.M of Appendix R, the licensee needs

to install penetration seals that have a 3-hour fireresistance rating. On October 20-24, 1986, a team of

Region III and NRR personnel performed an

announced inspection to determine the licensee's

implementation of and compliance with the

applicable requirements of 10 CFR Part 50,

Appendix R. In Inspection Report 50-263/86008

(DRS), the inspection team determined, "the licensee

does now meet Section III.M of Appendix R and this

'Open' item is now considered closed."

7.2.6 Peach Bottom Atomic Power

Station, Units 1 and 2

Silicone-based penetration seal materials are installed

in the plant.

In a letter of November 24, 1980, the staff informed

Philadelphia Electric Company, the licensee for

Peach Bottom Atomic Power Station, Units 1 and 2,

that the issue of penetration seals represented an

open item. By letter of November 14, 1986, the staff

issued an exemption from the technical requirements

of Section IH.M of Appendix R to the extent that

certain penetration seals contain combustible

material. In the safety evaluation supporting the

exemption, the staff stated that the penetration "seals

which contain combustible materials will provide an

equivalent level of protection to that required by

Section III.M of Appendix R." In the exemption, the

staff stated that "the application of the regulation in

this particular circumstance is not necessary to

achieve the underlying purpose of the rule.

Additionally, compliance with Section III.M

concerning the subject seals would result in costs that

are significantly in excess of those contemplated

when the regulation was adopted since it would result

in the complete removal and total replacement of all

seals in question."

7.2.7 Pilgrim Nuclear Power Station,

Unit 1

Silicone-based penetration seal materials are installed

in the plant.

In a letter of December 15, 1980, the staff

transmitted to Boston Edison Company, the licensee

for Pilgrim Nuclear Power Station, Unit 1, an SER

closing an open item regarding fire barrier

penetration seals. In that SER, the staff stated: "[t]he

licensee's proposed upgrading of penetration seals

will result in seals which meet the requirements of

Section III(M) [sic] of Appendix R to 10 CFR 50

and, therefore, are acceptable." The open item

regarding fire barrier penetration seals at Pilgrim was

closed before the effective date of Appendix R.

Therefore, Section III.M of Appendix R does not

apply to Pilgrim.

17 NUREG-1552, Supp. I
Conclusions

7.2.8 Point Beach Nuclear Plant, Units 1

and 2

Silicone-based penetration seal materials are installed

in the plant.

In a letter of November 24, 1980, the staff informed

Wisconsin Electric Power Company, the licensee for

Point Beach Nuclear Plant, Units 1 and 2, that the

issue of penetration seals was an open item and that

the licensee was required to comply with

Section I1I.M of Appendix R. In a letter of

January 22, 1981, the staff transmitted to the licensee

a supplemental SER, in which it concluded that the

penetration seals installed at Point Beach met the

criteria of Appendix A to BTP APCSB 9.5-1 and

were, therefore, acceptable. The open item regarding

fire barrier penetration seals at Point Beach was

closed before the effective date of Appendix R.

Therefore, Section Ill.M of Appendix R does not

apply to Point Beach.

7.2.9 H.B. Robinson Steam Electric

Plant, Unit 2

Silicone-based penetration seal materials are installed

in the plant.

In a letter of November 24, 1980, to Carolina Power

and Light Company, the licensee for H.B. Robinson

Steam Electric Plant, Unit 2, the staff stated that to

meet Section III.M of Appendix R to 10 CFR

Part 50, "the licensee should provide cable

penetration seals which utilize only noncombustible

materials and should be qualified by tests that are

comparable to those used to rate fire barriers." In a

letter of November 25, 1983, the staff issued an

exemption from the technical requirements of

Section Ill.M of Appendix R to 10 CFR Part 50, to

the extent that the acceptance criteria for penetration

seal qualification required that the temperatures

recorded on the unexposed side of the seal be below

the cable insulation ignition temperature. Neither the

exemption nor its supporting safety evaluation

addressed the fact that the penetration seals used

combustible materials.

7.2.10 Surry Power Station, Units 1 and 2

In a letter of November 24, 1980, to Virginia Electric

and Power Company, the licensee for Surry Power

Station, Units I and 2, the staff stated that "[t]o meet

the requirements of Section II.M of Appendix R to

10 CFR 50, the licensee should upgrade all unsealed

or inadequately sealed penetration openings to

provide a 3-hour ASTM E-1 19 fire rated penetration

seal where the fire rating of the barrier penetrated

would be 3 hours." In a letter of December 18, 1980,

the staff transmitted to the licensee a supplemental

SER in which it concluded that the penetration seals

installed at Surry met the criteria of Appendix A to

BTP APCSB 9.5-1 and were, therefore, acceptable.

The open item regarding fire barrier penetration seals

at Surry was closed before the effective date of

Appendix R. Therefore, Section III.M of

Appendix R does not apply to Surry.

7.2.11 Vermont Yankee Nuclear Power

Station

In a letter of January 13, 1978, the NRC issued

Licensing Amendment 43 to Vermont Yankee

Nuclear Power Station's operating license. In this

amendment, the NRC identified Item 3.1.8, "Cable

penetrations do not have a fire rating and do not

provide adequate protection." In a letter of

November 24, 1980, to Vermont Yankee Nuclear

Power Corporation (VYNPC), the licensee for

Vermont Yankee, the staff again noted that Item

3.1.8 was unresolved owing to the lack of supporting

qualification tests. In a letter of December 19, 1980,

to the NRC, VYNPC stated: "Vermont Yankee

intends to maintain its commitment to provide 3-hour

rated fire barrier penetration seals."

In a letter of December 31, 1980, Region I followup

inspection 50-271/80-18 of Vermont Yankee fire

barrier penetration seals, three inspection items were

opened concerning the original "Item 3.1.8, Fire

Barrier Penetrations." The open items were 80-18-

01, an untested configuration; 80-18-02, questions on

materials used to construct the penetration seals; and

80-18-03, a commitment to replace/upgrade existing

penetration seals.

In a letter of December 23, 1981, a Region I

Inspector reviewed open item 80-18-02, found the

licensee actions acceptable, and closed the item. In a

letter of April 22, 1982, Region I Inspectors reviewed

open items 80-18-01 and 80-18-03, found the

licensee actions acceptable, and closed the open

items. Additionally, in an internal NRC

memorandum dated April 16, 1982, to Thomas

Novak, Assistant Director for Operating Reactors,

from William Johnson, Assistant Director of

Materials and Qualifications Engineering, Johnson

stated: "open item 3.1.8 is now considered closed

NUREG-1552, Supp. 1 18
Staff Recommendations

based on VYNPC's commitment to comply with

Section III.M of Appendix R."

7.3 Summary

On the basis of its review of letters that the staff sent

to the licensees of plants that were operating before

January 1, 1979, after Appendix R was approved but

before it became effective, it appeared that

Section III.M of Appendix R applied to 15 nuclear

power plants. However, on the basis of the detailed

review summarized above, the staff found that

Section III.M of Appendix R applied to Duane

Arnold, H.B. Robinson 2, Maine Yankee,

Monticello, Peach Bottom 2/3, and Vermont Yankee.

Of these plants, the staff has granted exemptions for

H.B. Robinson 2 and Peach Bottom 2/3. On the

basis of its review of docketed information, the staff

could not determine how the penetration seal open

items were resolved at Duane Arnold and Maine

Yankee. Because the licensee has permanently shut

down Maine Yankee and is currently

decommissioning it, the staff will not pursue this

issue at Maine Yankee. The other plants discussed

above, FitzPatrick, Pilgrim, Point Beach 1/2, and

Surry 1/2, resolved the penetration seal open item

before the effective date of Appendix R. Therefore,

Section III.M of Appendix R does not apply to these

plants.

8 RECOMMENDATIONS IN

THE FINAL STAFF REPORT

8.1 Introduction

In SECY-96-146, "Technical Assessment of Fire

Barrier Penetration Seals in Nuclear Power Plants"

(July 1, 1996), the staff informed the Commission

that the Office of Nuclear Reactor Regulation (NRR)

had completed the subject assessment and forwarded

to the Commission a copy of its final report entitled,

"Technical Assessment of Fire Barrier Penetration

Seals in Nuclear Power Plants" (June 14, 1996). In

its final report, the staff recommended the following:

(1) Revise the NRC fire protection guidance

documents to reflect the current National Fire

Protection Association (NFPA) position on

testing laboratories.

(2) Remove the noncombustibility criterion from

Appendix R to 10 CFR Part 50 and Standard

Review Plan (SRP) Section 9.5,1.

(3) Develop and issue guidance for comparing fire

test configurations to as-built configurations.

(4) Make this technical assessment report available

to the general public and industry by placing it in

the NRC Public Document Room and issuing an

information notice publicizing its availability.

In its final report, the staff also noted that it was

preparing the new Fire Protection Functional

Inspection (FPFI) Program that it had described in

SECY-95-034, "Status of the Recommendations

Resulting from the Reassessment of the NRC Fire

Protection Program" (February 13, 1995). The staff

stated that it would present guidance for inspecting

fire barrier penetration seal programs in the FPFI

procedures and guidelines for use by NRC inspectors

on an as-needed basis.

8.2 Status

8.2.1 Recommendations 1, 2, and 3

(Pending)

Recommendations 1, 2, and 3 involved revising the

NRC fire protection regulation (Appendix R) and

review guidance (SRP). In its final report on

penetration seals, the staff indicated that

implementation of the recommendations would be

useful to the industry, but did not identify technical

or safety bases that justified an immediate need to

implement them.

The NRC staff, under the Regulatory Improvements

Program, is considering a performance-based, riskinformed fire protection regulation. After the staff

issued its final report "Technical Assessment of Fire

Barrier Penetration Seals in Nuclear Power Plants"

(June 14, 1996), it issued several Commission papers

regarding fire protection rulemaking. Most recently,

in SECY-98-058, "Development of a Risk-Informed

Performance-Based Regulation for Fire Protection at

Nuclear Power Plants," March 26, 1998, the staff

provided rulemaking options for a performancebased, risk-informed fire protection regulation;

proposed to develop a comprehensive regulatory

guide for reactor fire protection; and proposed to

revise Section III.M of Appendix R to 10 CFR Part

50 to resolve the combustible penetration seal issue

(see Section 5.8 of NUREG-1552).

In a staff requirements memorandum of June 30,

1998, the Commission directed the staff to develop

the comprehensive regulatory guide and to pursue

19 NUREG-1552, Supp. 1
Conclusions

rulemaking to amend Section III.M of Appendix R to

eliminate the requirement that penetration seal

materials be noncombustible. Later, in a letter of

July 20, 1998, from R.L. Seale, Chairman, ACRS, to

Chairman Jackson, the ACRS stated its agreement

with the Commission direction to amend

Section III.M of Appendix R. The staff will

implement the Commission's direction. This will

satisfy the intent of Recommendations 1, 2, and 3.

8.2.2 Recommendation 4 (Complete)

In July 1996, the staff published NUREG- 1552,

"Fire Barrier Penetration Seals in Nuclear Power

Plants." This action completed Recommendation 4.

8.2.3 FPFI Program (Complete)

The staff is currently using its FPFI procedures to

conduct the pilot FPFI program. The NRC's routine

fire protection inspection procedures are in the NRC

Inspection Manual, Inspection Procedure 64704,

"Fire Protection Program." In September 1997, the

staff revised these procedures to provide more

specific guidance for inspecting the seals and

establishing their functionality.

9 PUBLIC COMMENTS ON

DRAFT NUREG-1552,

SUPPLEMENT 1

On July 13, 1998, the staff noticed in the Federal

Register (Volume 63, Number 133) that it was

accepting public comments on Draft NUREG-1552,

Supplement 1. The staff also made the report

available on the World Wide Web at the NRC

website. During the public comment period, the staff

received two letters in response to the draft report. In

a letter dated September 11, 1998, the Nuclear

Energy Institute (NEI) stated agreement with the

conclusions of this report. In a letter dated

September 16, 1998, the Nuclear Information and

Resource Service (NIRS) stated disagreement with

the conclusions of the report. Neither of the letters

included new technical or safety information.

Therefore, the comments did not result in changes to

this report. These letters are part of the public record

and are available at any NRC Public Document

Room.

March 1975, nuclear power plant licensees have

made significant improvements in their fire

protection programs. These improvements,

especially the adoption of the defense-in-depth

concept of echelons of fire protection, have reduced

both the probability and the potentially adverse

consequences of nuclear power plant fires. Using

documented industry operating experience, the staff

carefully and objectively evaluated issues associated

with fire barrier penetration seals. The staff

considered the potential safety and risk significance

of potential penetration seal deficiencies and the use

of compensatory measures for any potential

degradation in the fire protection effectiveness of

seals.

For the reasons discussed in Sections 3 through 5, the

staff considers that the relative safety significance of

the subject fire barrier penetration seal concerns is

low. Even assuming that certain fire barrier

penetration seals are deficient, it does not follow that

the deficiencies indicate the absence of adequate

protection. The Commission has explained that

[W]hile it is true that compliance with all

NRC regulations provides reasonable

assurance of adequate protection of the

public health and safety, the converse is not

correct, that failure to comply with one

regulation or another is an indication of the

absence of adequate protection, at least in a

situation where the Commission has

reviewed the noncompliance and found that

it does not pose an "undue risk" to the

public health and safety.6

The failure to have fire barrier penetration seals that

meet the criteria specified by the NRC fire protection

guidance documents does not necessarily indicate

that a plant is unsafe.

On the basis of everything it found and considered, it

is the staff's judgment that, overall, the issue of

potential fire barrier penetration seal deficiencies

does not adversely affect safety. For the reasons

given in this paper, typical penetration seal

deficiencies do not necessarily equate to a lack of

adequate protection or result in undue risk to public

health and safety.

On the basis of the reassessment documented here,

10 CONCLUSIONS

Since the fire at Browns Ferry Nuclear Plant in

6

Ohio Citizens for Responsible Energy, DPRM 88-4,

28 NRC 411 (1988).

NUREG-1552, Supp. 1 20
Conclusions

the staff concluded that the actions it took in 1988

and 1994 to alert licensees to potential penetration

seal problems increased industry awareness of such

problems and resulted in more thorough

surveillances, maintenance, and corrective actions.

The staff also concluded that the general condition of

penetration seal programs in industry is satisfactory.

The staff will continue its reviews and inspections of

penetration seal programs. The staff expects that

plant-specific deficiencies may occasionally be found

during licensee surveillances and NRC reviews and

inspections. However, potential penetration seal

problems are understood; industry consensus fire test

standards are available and are followed; and fire test

results and qualified fire-resistant seal materials and

designs are available. Therefore, licensees have the

means to correct problems, and continued staff

oversight will continue to ensure corrections on a

case-by-case basis. In addition, the fire protection

defense-in-depth concept provides reasonable

assurance that deficiencies will not present an undue

risk to public health and safety before they are found

and corrected.

The results of this assessment, which used

information that the staff had not considered in the

evaluation documented in NUREG-1552, "Fire

Barrier Penetration Seals in Nuclear Power Plants,"

have reinforced the staff's earlier conclusion that

RTV silicone foam penetration seals like other types

of penetration seals installed in US nuclear plants,

provide reasonable assurance that a fire in a specific

fire area or zone will be confined to the area of

origin.

During the 454th meeting of the Advisory Committee

on Reactor Safeguards (ACRS), July 8-10, 1998, the

staff presented the results of the assessment

documented in this supplement to NUREG- 1552 to

the ACRS. The ACRS provided its views regarding

the efforts of the NRC staff and the nuclear industry

to resolve issues related to fire barrier penetration

seals in a letter of July 20, 1998, from R.L. Seale,

Chairman, ACRS, to Chairman Jackson. The ACRS

noted that it is clear that, overall, the NRC staff and

the licensees have the issues of fire barrier

penetration seals well in hand and that the efforts of

the staff and the licensees have been successful in

addressing the problems of the past.

In sum, it is the staffs opinion that continued licensee

attention to existing penetration seal programs and

continued NRC inspections are adequate (1) to

ensure that penetration seal problems are discovered

and resolved and (2) to maintain public health and

safety. To provide added assurance of this, during

the assessment documented in this report, the staff

issued Information Notice 97-70, "Potential

Problems With Fire Barrier Penetration Seals,"

September 19, 1997, and revised the NRC fire

protection core inspection module to provide more

specific inspection guidance to NRC inspectors

regarding fire barriers and fire barrier penetration

seals. The staff will continue to assess new

information regarding penetration seals for new

insights and appropriate opportunities for additional

actions by the staff or the industry.

21 NUREG-1552, Supp. 1

Appendix D

Acronyms and Abbreviations

BNL Brookhaven National Laboratory

CDF core-damage frequency

CDR construction deficiency report

DRS division of reactor safety

ICMS Insulation Consultants & Management Services, Incorporated

IF inspection followup item

KG&E Kansas Gas & Electric

0I Office of Investigations (NRC)

ORNL Oak Ridge National Laboratory

PVC polyvinyl chloride

RTV room temperature vulcanizing

SER safety evaluation report

SRM staff requirements memorandum

URI unresolved issue

VYNPC Vermont Yankee Nuclear Power Corporation

WCNGS Wolf Creek Nuclear Generating Station

D-1 NUREG-1552, Supp. 1

Appendix F

Licensee Event Reports Submitted by Year

(1987 Through September 1998)

1987 12 16 3

1988 9 12 4

1989 12 14 9

1990 8 11 5

1991 7 8 10

1992 3 8 8

1993 7 8 6

1994 6 6 5

1995 4 4 3

1996 5 5 1

1997 4 3 3

1998 4 5 3

TOTAL 46 100 62

F-1 NUREG-1552, Supp. 1

Appendix G

Summary of Reported Problems

(1987 Through September 1998)

Penetrations unsealed 10 6 6 4 1 3 4 1 1 1 1 38

Seal breached and not repaired 4 1 1 2 - 2 2 1 - 1

Internal conduit sea] not installed 1 1 3 1 - 1 2 -

jTotal - S4n Not Installed or Brepache~d 15 8 10 7 1 6 4 3 2 1 1

15 8 10 7 1 6 4 3

Voids, gaps, splits, shrinkage, cell structure 1 4 3 4 2 2 2 1 19

C) Inadequate seal thickness 1 2 1 - - 3 2 2 - 1 - 2 14

Seal not properly installed - - 1 1 2 2 2 2 - 1 - 2 13

Incorrect seal material installed 1 2 1 - 1 - - 1 - - -7

Temporay seal not replaced 1 - 1 - - 1 1 1 - 5

1 1 1 1 1 I 5

4 9 7 5 6 9 5 7 1 3 1 6

1 5 2 3 1 1 1 1 3 1

C)

Seal degraded or damaged 2 2 1 1 3 1 1 11

Missing or damaged damming boards 111 - 1 1 1 - 6

IITotal - Seal Dejiraded or Thtmap-ed 3 3 2 1 4 1 1 2 17

Totals 23 25 21 15 9 19 10 12 5 8 3===..

Appendix H

Summary of Licensee Event Reports

(1987 Through September 1998)

nntc (nlante nnPrntincr nrinr n Tn•innI, I 1Q7Q nro hn

PLANT

ANO 2

FitzPatrick

Fort St. Vrain 1

Monticello

Nine Mile Point 2

Quad Cities 1/2

River Bend Station

Salem 1/2

Susquehanna 1

TMI-1

WNP2

LER NO.

87-001-00

87-011-00

87-011-01

87-006-00

87-006-01

87-011-00

87-016-00

87-016-01

87-018-00

87-028-00

87-021-00

87-007-00

87-011-00

87-003-00

87-004-00

87-029-00

87-030-00

ACCESSION NO.

8703180073

8709020094

8802030335

8704160030

8705180247

8705260063

8703310063

8707010536

8704150327

8803080281

8711170189

8706150188

8705050296

8705080327

8705130234

8710220153

REPORT

2 conduits missing internal seals.

224 out of a total of 16,000 penetrations

found unsealed.

Updated 87-011-00. Installation

specification, surveillance procedures

revised.

Unsealed penetrations and degraded seals.

Updated 87-006-00.

1 unsealed penetration.

1 penetration sealed with incorrect seal

material. Similar seals inspected.

Unsealed penetrations and breached seal.

1 breached seal.

Several damaged seals, several unsealed

penetrations, and 7 inadequate temporary

seals.

2 unsealed penetrations.

1 unsealed penetration.

1 unsealed penetration.

1 unsealed penetration.

Design drawings were incomplete, 2

unsealed penetrations, and 1 seal not

included in surveillance procedure.

1 seal not repaired after breaching to remove

cables.

Penetrations not sealed.

H-1 NUREG-1552, Supp. 1
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Wolf Creek 87-001-00 8702100286 1 seal found breached.

87-010-00

87-010-01

87-010-02

8703250035

8707150537

8804050361

Several seals found breached. Surveillance

procedure enhanced, personnel trained.

Fire protection program to be

upgraded. Nonconforming silicone foam

seals found (missing or damaged damming

boards, inadequate seal thickness, voids,

shrinkage).

Final update of 87-010-00. Performed

sample inspection program by removing

damming boards from 40 seals; 13 rejected

for insufficient foam thickness, 9 rejected

for voids and shrinkage. Performed 100%

inspection (1700 seals). Repaired and

reworked more than 600 seals.

Ginna 1 88-009-00 8811090368 Several degraded seals and seals with

incorrect seal material found.

H.B. Robinson 2 88-018-00 8810070343

88-018-01

McGuire 1 88-030-00

Nine Mile Point

88-030-01

88-009-00

88-009-01

88-009-02

8906190260

8811150235

89022700381

8804280564

9006180174

9008230138

101 cable tray penetration seals inspected.

38 not sealed inside tray covers due to

inadequate installation procedure.

Procedures revised.

Updated 88-018-00.

Review conducted in response to IN 88-04.

96 seals declared inoperable due to lack of

test documentation.

Updated 89-030-00. Seals qualified by test.

Procedures improved.

Replaced by 88-009-01.

Task force formed and 100% seal

inspection initiated. 13 seals did not have

adequate supporting documentation. Fire

protection program enhanced.

14 seals did not have adequate

documentation.

NUREG-1552, Supp. 1 H-2
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

North Anna 1/2 88-007-00 8802290350 Eight fire barrier penetration seal breaches

were identified. These breaches were

repaired.

Oconee 1/2/3 88-005-00 8806270349

River Bend Station 88-009-00

88-009-01

88-009-02

Salem 1/2 88-013-00

88-014-00

8804050384

8805100011

8808310152

8809140180

8810040008

8806300078

8811170093

8812150039

8906050115

8907190362

Review conducted in response to IN 88-04.

100% seal inspection revealed 188

inoperable seals due to inadequate

documentation. Procedures revised.

3 unsealed penetrations and one inadequate

seal found.

1 unqualified penetration seal found.

Unsealed conduits, unsealed penetrations,

breached seals, and incompletely sealed

penetrations found.

Several silicone foam seals did not conform

to correct color and cell structure. Existed

since original installation. Installation

procedure revised. 100% of foam seals

inspected to verify compliance with

installation criteria.

Purpose of LER was to report missed

surveillance for inoperable penetration seals.

Also, summarized seals inoperable because

of degradation, wrong seal material,

shrinkage, and unsealed penetrations.

1 seal found that did not conform to

standard design.

Unsealed penetrations found.

100% seal inspection. Found unsealed

penetrations, missing damming boards, and

silicone foam seals with voids.

Updated 88-030-00. Damming boards

removed from seals for inspection. Found

99 seals with voids, 123 seals that differed

from typical design details, 17 seals that

deviated from vendor requirements, and 19

unsealed penetrations.

Updated 88-030-00. Installation procedures

changed.

Waterford 3 88-011-00

88-025-00

88-030-00

88-030-01

88-030-02

H-3 NUREG-1552, Supp. 1
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Waterford 3

(continued)

88-030-03

WNP2 88-008-00

9109060034

8805030155

9302220125

Updated 88-030-00. 228 seals to

be reworked.

11 inoperable seals due to unapproved

configuration, inadequate seal thickness,

seals improperly repaired. Updated seal

database. 100% documentation review

and seal inspection.

88-008-01 Updated 88-008-00.

ANO 1 89-003-00 8903280098 2 penetrations sealed with unqualified

material.

Big Rock Point 89-006-00

Calvert Cliffs 2

Clinton 1

Dresden 2

89-006-01

89-002-00

89-002-01

89-006-00

89-030-00

89-014-00

89-014-01

89-001-00

8908240314

9004130265

8904050315

8911210052

8902230041

8911280062

8909250113

8912270289

8902070157

Licensee initiated penetration seal

verification program in response to

IN 88-04 and IN 88-56. 1 seal breached and

not repaired, 1 seal inadequately installed.

3 inadequate seals and 1 seal with a gap

were found.

Conduit missing internal seal.

Updated 89-002-00.

3 conduits missing internal seals.

1 unsealed penetration. Procedures

improved.

4 seals did not meet cell structure criteria.

Updated 89-014-00, 2 seals deleted from the

LER.

1 temporary seal found inoperable. Seal

upgrade program conducted in response to

IN 88-04.

Several unsealed penetrations

found during seal upgrade program.

Fort St. Vraln

Haddam Neck

89-001-01 9101140199

NUREG-1552, Supp. 1 H-4
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Monticello 89-001-00 8902080493 6 unsealed penetration found. 100%

89-013-00

89-013-01

North Anna 1/2 89-003-00

Palisades 89-024-00

River Bend Station 89-005-00

89-010-00

89-010-01

89-010-02

89-010-03

89-010-04

89-010-05

89-011-00

89-011-01

8908070189

9001100234

8902140025

8912260122

8903240060

8904260064

8906190263

8909080115

9008060246

9401060365

9409140061

8910170274

8912270219

inspection initiated.

Several unsealed penetrations found.

Updated 89-013-00. Inspection completed.

No additional deficiencies found.

A void was discovered in one fire barrier

penetration seal. A fire watch was put into

place, and the void was then repaired.

Inspection conducted in response to

IN 88-04. 1 unsealed penetration found.

Void found in 1 low-density silicone

elastomer seal. Sample of similar seals

inspected.

1 unsealed penetration and 4 conduits

without internal seals.

Updated 89-010-00. Task force formed.

Updated 89-010-00.

Updated 89-010-00. Based on results of

sample inspections, conducted 100% seal

inspection.

Completed program end of 1993. 3385

penetration seals inspected; 1961 found

unacceptable. Reworked or reevaluated

deficient seals. Deficiencies included:

gouged or damaged damming material,

shrinkage of silicone foam, inadequate seal

thickness, cuts in boot material, and

inadequate documentation.

Updated 89-010-00.

Seabrook 3 unsealed pipe penetrations.

Updated 89-011-00. Initiated 100% seal

inspection, developed comprehensive seal

program, clarified surveillance

requirements.

H-5 NUREG-1552, Supp. 1
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO.

Susquehanna 89-019-00 8907060047

REPORT

Damaged seals determined to be inoperable.

Consistent inspection and acceptance

criteria developed.

ANO 1 90-004-00 9007090045

90-004-01 9105160074

90-004-02 9204300230

90-017-00

90-023-00

Fort Calhoun 1 90-022-00

90-022-01

90-022-02

9008200077

9012120354

9010170151

9101090184

9102120021

9002220099

9006050277

9002220099

9103270201

9008280179

1 unqualified penetration seal.

Small voids around grout joint.

In response to IN 88-04, found 2 seals not

properly installed.

Void in large grout blockout seal.

1 unsealed penetration.

In response to IN 88-04, assessed and

walked down 100% of seals. Found about

460 of 3500 seals may be inoperable

because documentation did not exist or

installed configurations did not match

documentation.

Updated 90-022-00. Found 92 more

potentially inoperable seals.

Updated 90-022-00. Found more potentially

inoperable seals and resolved others. Final

count of potential inoperable seals due to

lack of documentation was 441 out of 3500.

The licensee performed evaluations,

repaired, and replaced seals. Upgraded

procedural controls and drawings.

Missing internal conduit seal.

1/4" plastic tube found passing through

(breaching) a seal.

1 unsealed penetration.

Performed 100% inspection, 14 additional

inoperable seals found.

Seal breached and not resealed.

H.B. Robinson 2 90-003-00

90-008-00

90-010-00

90-010-01

Monticello 90-009-00

H-6
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO.

Palo Verde 1/2/3 90-009-00 9010310125

90-009-01 9208200192

REPORT

Performed 100% inspection of Unit 2,

found about 256 questionable seal attributes

out of 2000 examined. Deficiencies

included unsealed penetrations, seal

shrinkage, improperly installed seals, and

gaps in damming materials.

Performed 100% inspection of Units 1 and

3. Found about 1437 questionable seal

attributes out of more than 10,000

examined. Deficiencies included unsealed

penetrations, seal shrinkage, improperly

installed seals, and gaps in damming

materials.

In response to IN 88-56, found silicone

foam seals with splits.

Destructive testing revealed 17 similar seals

with splits.

Removed penetration seal around HVAC

damper as a part of modification and did not

replace.

Updated 90-019-00. Found 1

additional unsealed penetration.

Trojan 90-022-00

90-022-01

Waterford 3 90-019-00

9007230142

9012060223

9101150362

9103040377

9109190291

90-019-01

90-019-02 Updated 90-019-00.

ANO 2 91-016-00 9110250001

Big Rock Point 91-001-00

91-001-01

91-024-00

91-024-01

9102200140

9103260311

9112170535

9403230046

FitzPatrick

Seal not installed properly (filled with rags

rather than grout).

Voids found in 3 seals in response to

IN 88-56.

8 more seals found with voids.

7 penetrations sealed with incorrect

material.

Performed 100% inspection. Deviations

from design were found in 39% of 7200

seals inspected. 15% required cosmetic

repairs. Problems included: inadequate seal

thickness, installation, or seal material,

unsealed penetrations, voids, holes, edge

curl, and separation of foam. All seals were

restored to design condition or evaluated.

H-7 H-7 NUREG-1552, Supp. I
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Monticello 91-021-00 9111050217 Seal damaged due to pipe movement.

Peach Bottom 2

Point Beach 1

Sequoyahl

91-013-00

91-007-00

91-013-00

91-013-01

91-016-00

91-016-01

9106190190

9107300239

9107030303

9108050172

9108190108

9202140203

2 seals contained voids and uncured sealant

material.

2 seals left inoperable after design

modification.

Improperly installed seal around a conduit

Updated 91-013-00.

9 mechanical seals inoperable due to

pipe movement.

Schedule update.

Duane Arnold 92-003-00 9203190032

92-007-00

92-007-01

92-008-00

92-006-00

Haddam Neck

Trojan

9206150398

9208040177

9203270186

9203090105

9205110198

9206080031

9209300187

1600 seals inspected. 1 penetration found

unsealed since design modification.

Program improvements made to minimize

likelihood of recurrence.

6 penetrations unsealed since original plant

construction. Found during first time

inspection using new, enhanced inspection

program.

Updated 92-007-00. Improved inspection

schedule.

I seal inoperable. Silicone foam had been

removed and replaced with ceramic fiber.

2 seals missing damming boards and

inadequate silicone foam thickness since

original installation (1979). Corrective

actions included inspecting all similar seals.

Inspection of similar seals found 1

additional seal without damming board.

1 seal not repaired and I breached seal not

resealed. Fire barrier inspection procedures

were upgraded.

During 18-month surveillance found grout

missing from I seal. Inspectors retrained.

92-006-01

92-011-00

92-026-00

H-8
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Trojan

(continued)

92-026-01

92-026-02

92-026-03

92-026-04

92-026-05

92-031-00

92-034-00

9211030238

9211160031

9211300072

9301050162

9310250073

9211190123

9301250264

1" diameter hole found through a

silicone foam seal.

1 seal with inadequate grout thickness and 1

grout seal damaged.

2 conduits did not have internal seals.

4 seals found with inadequate thickness of

silicone foam and 1 seal with inadequate

thickness of grout. Personnel retrained.

Updated 92-026-00. Degraded

penetration seals resulted from personnel

errors and inadequate procedural controls.

Extensive procedural controls implemented.

1 grout seal degraded and inadequate grout

thickness.

A small gap was found between a grout seal

and the penetrating pipe. Two grout seals

were degraded and 1 of these had

inadequate grout thickness.

Brunswick 93-006-00 9304060055 During 100% inspection, found 9

unqualified seals.

Haddam Neck

Indian Point 3

LaSalle 1

Millstone I

93-003-00

93-029-00

93-009-00

93-006-00

93-001-00

93-002-00

9305030266

9309240036

9303290295

9307200165

9302230261

9303180036

Found 1 unsealed penetration and 1 seal

with a temporary seal

In response to IN 88-04, initiated seal

inspection program. 2 seals found that did

not conform to tested configuration.

3 unsealed penetrations. Sample of

penetrations inspected. No additional

deficiencies found.

1 unsealed penetration found using

improved inspection procedure.

Trojan 1 unsealed penetration.

2 grout seals had inadequate thickness.

H-9 NUREG-1552, Supp. 1
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO.

Vermont Yankee 93-001-00 9301220246

REPORT

In 1992, all seals containing insulated lines

were declared indeterminate. Inspection

revealed 1 penetration with inadequate seal

thickness and 3 others that did not conform

to design details. Licensee notified industry

through Nuclear Network.

Updated 93-001-00. Boot seals to be used

for some pipe penetrations.

Updated 93-001-00. All seals to be

inspected using enhanced surveillance

procedure. Design change implemented.

93-001-01

93-001-02

9303090037

9307140180

Cooper 94-008-00 9405240103

Diablo Canyon 1/2 94-001-00 9403090054

Improperly installed seal found. Seal was

repaired.

Seals may not meet required fire rating due

to lack of damming boards. All seals

declared indeterminate. Program to qualify

and repair seals.

Maine Yankee

Millstone 2

Vermont Yankee

94-001-01

94-010-00

94-010-01

94-035-00

94-018-00

94-018-01

94-002-00

9408310118

9408180131

9508290022

9412060226

9501190145

9506140431

9403230142

2 conduits without internal seals found.

Conduit seals missing. The conduits were

part of a new installation. They were sealed

and inspected.

Breached/missing internal conduit seal.

Seals installed.

2 seals degraded. One was missing caulk

and the other had a 3/8" void in the brick

and mortar seal.

Updated 94-001-00.

Updated 94-018-00.

WNP2 Due to an employee concern, licensee found

original installation of seals, including

written procedures, design configuration,

and analysis less than adequate.

Deficiencies included: inadequate thickness,

PVC sleeves and seals that exceeded design

specifications. Seals declared inoperable.

Corrective actions included walkdowns,

engineering evaluations, and establishing

supporting fire test documentation.

H-10
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

WNP2 94-002-01 9407130092 Updated 94-002-01.

(continued)

Calvert Cliffs 1 95-004-00 9509210118

Haddam Neck 95-001-00 9502230065

3/4" gap (breach) found in a seal. Seal

repaired, seal surveillance procedure

upgraded.

1 degraded grout seal and 1 unsealed

penetration found. 18-month surveillance

revealed 4 inoperable seals and 3 unsealed

penetrations. 100% field walkdown

as corrective action.

Susquehanna

Vermont Yankee

95-001-01

95-011-00

95-004-00

950808017

9511070336

9505030454

Updated 95-001-00.

Review of fire test reports revealed that hose

stream test did not meet commitment. Staff

inspected this issue January 1996.

Improperly repaired seal declared

inoperable. Seal was repaired.

D.C. Cook 2 96-004-00 9604180325 Seal found degraded/damaged when a

100% seal inspection was completed.

Diablo Canyon 1/2 96-011-00

96-011-01

96-017-00

9609170363

9706040331

Maine Yankee 9608060017

Epoxy grout seals untested and, therefore,

outside design basis.

Reported qualification of epoxy grout seals

by test.

Fire barrier penetration inspection revealed

seals missing damming boards, inadequate

seal thickness, and temporary seals. No fire

tests to support some configurations.

Attributed to weaknesses in original

installation QC, and surveillance

procedures.

Updated 96-017-00.

Fire barrier evaluations not documented for

two seals. Penetration seal program

weaknesses noted. Commitment made to

develop a design-basis document for fire

barriers.

96-017-01

96-009-00

9608060017

Palisades 9608200212

H-11 NUREG-1552, Supp. 1
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Vermont Yankee 96-026-00 9611130511 Two seals imnronerlv installed durine

96-026-01 9703280401

original installation.

Updated 96-026-00.

Fermi 97-014-01 9804140118

St. Lucie 97-004-00 9707150008

9709040179

Penetration seals were found missing from

the auxiliary building wall and parallel

turbine building wall. These walls were

rated fire barriers. 16 penetrations were not

sealed at the auxiliary building wall, and 4

were unsealed at the turbine building wall.

The unsealed penetrations were sealed to

comply with Appendix R.

Two-sided cable tray firestop was

discovered to be missing ceramic fiber

insulation between cables. All cable tray

fire stops were declared inoperable, and will

be upgraded accordingly.

15 penetration seals were declared

inoperable as they could not be bounded by

supporting fire tests. The seal manufacturer

(Promatec) did not supply proper

qualification documentation. Seals will be

re-worked to meet applicable configuration

drawings.

97-008-00

Clinton 98-021-00 9808250144 Cracks were discovered in a penetration seal

during a "NUREG 1552" walkdown of

penetration seals. Some cracks went

completely through the seal. The licensee is

inspecting other seals, repairing any that

need repair and revising procedures.

Licensee issued 10 CFR Part 21 notification

concerning the seal material.

H- 12
Summary of Licensee Event Reports

PLANT LER NO. ACCESSION NO. REPORT

Prairie Island 98-003-00 9806300550 Penetrations were discovered that were not

sealed. The openings were to be evaluated

and then sealed according to plant

procedures.

Vermont Yankee 98-001-00 9803020316

98-001-01

98-008-00

98-008-01

98-014-00

98-014-01

9805210006

9805060322

9808240312

9806250116

9808180028

Following work potentially affecting a

penetration seal, the seal was inspected and

found not to conform to the tested

configuration for a 3-hour seal. The grout

seal was inadequately installed during the

construction of the plant and was to be

repaired. Other grout block-out seals were

to be inspected.

Updated 98-001-00.

Penetration seal was found to have 3" of

seal depth where 6" was required for a

3-hour rating (silicone elastomer). Root

cause was determined to be inadequate

QA/QC on original installation.

Updated 98-008-00.

VY discovered 2 non-conforming seals.

One seal was inadequately repaired with 7"

of silicone foam rather than the required 12"

for a 3-hour rating. The other seal was

improperly installed with 7" of foam rather

than the required 12". The seals were

repaired.

Updated 98-014-00.

H-13 NUREG-1552, Supp. 1

Appendix I

NRC Inspections (March 1988 Through August 1998)

(Annendix R olants (olants oneratiny onrior to January 1. 1979) are shown in bolh

Beaver Valley 1

Beaver Valley 2

93-12,

93-13

07/02/93 Narrow Minor Licensee could not verify that eight internal conduit seals were installed. A fire watch was

posted until the seals were installed per procedures. I t 4. t 4.

Browns Ferry 1/2/3 89-28 09/15/89 Narrow None During a fire protection inspection, inspectors opened followup item 89-28-03 to track

completion of penetration seals for electrical raceways and mechanical fire barrier

penetrations. Inspectors found the licensee's penetration seal program to be acceptable.

90-11 05/11/90 Narrow None Inspectors closed followup item 89-28-03 regarding installation of penetration seals.

92-11 05/01/92 Narrow None Inspectors reviewed procedures for maintenance of fire barrier penetrations. Inspection

results for fire rated barriers were also reviewed. No discrepancies were noted.

95-60 12/12/95 Broad None Inspector reviewed typical mechanical, electrical conduit, and cable tray penetration seal

installation procedures, drawings, details, quality control (QC) records, quality assurance

(QA) records, engineering evaluations, and qualification test documentation. Inspector

did not find any discrepancies.

98-01 03/24/98 Broad None Inspectors reviewed the licensee's penetration seal program and determined that it was

adequate. Licensee had evaluated numerous seals to demonstrate that they were adequate

for their given applications. Licensee was performing 100% seal inspection every 18

months. This was considered a strength in the fire protection program. I I. 4. 4 1.

Brunswick 1/2 92-31 10/26/92 Narrow None Inspectors observed performance of a portion of the periodic inspection of fire barrier

seals. Inspectors noted the inspections were detailed, and that the licensee had initiated a

re-inspection effort for fire barriers, which was seen as a positive initiative for selfidentification and corrective action of fire barrier inspection program deficiencies. In

addition, inspectors noted that penetration seals were acceptable during a general plant

walkdown.

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WV

93-08 03/25/93 Narrow None During a fire protection inspection, inspectors reviewed the licensee's fire barrier

reinspection program and found it to be adequate.

93-38 09/10/93 Narrow None Inspectors closed [ER 92-12-01 which concerned inadequate fire barrier wall gap

material. As part of the close-out actions, the licensee conducted a detailed review and

inspection of fire barriers and penetration seals during a Unit 1 outage.

97-07 06/20/97 Narrow None Inspectors noted that penetration seals were acceptable during a general plant walkdown.

97-13 01/23/98 Broad Minor -Inspectors reviewed a sample of silicone foam fire barrier peneration seals including seal

design and testing. Inspectors opened IF 97-13-04 to track missing penetration seal

testing documentation.
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Byron 1/2 92-007 04/13/92 Narrow None Inspector observed fire penetration seals while conducting a plant walkdown and did not

observe any problems.

0 Callaway 94-012 12/06/94 Narrow None Inspectors noted that barrier seals in the plant were in generally good condition.

Calvert Cliffs 1/2 94-15 05/06/94 Narrow None Inspectors noted that the licensee has scheduled a review of all plant penetrations to verify

the adequacy of the installations. Inspectors concluded that there were no safetysignificant issues associated with the penetration seals.

93-99 07/10/95 Broad None SALP report concluded that licensee lacked a formal engineering evaluation for

qualification of certain fire barrier penetration seal materials.

95-08 10/16/95 Broad Minor Cork expansion joints found to be inadequate fire barriers; polysulfide caulk found to be

inadequate sealant for a fire-rated barrier. These deficiencies resulted in a Severity'Level

IV violation.

96-201 05/06/96 Broad None TIle staff inspected the fire barrier penetration seal program and concluded that the

licensee had an acceptable program. Ongoing licensee efforts to improve the penetration

seal program were seen as positive.

Catawba 1/2 91-22 11/04/91 Narrow None During a fire protection inspection, inspectors did not identify any discrepancies in fire

barrier penetration seal installations while on a plant walkdown.

97-07 05/23/97 Broad None Inspectors reviewed licensee's evaluations and corrective actions related to IN 94-28,

"Potential Problems with Fire Barrier Penetration Seals."

98-07 07/27/98 Broad Minor Inspectors reviewed licensee's corrective actions for penetration seals that were found

with gaps and lack of proper sealant material. Inspectors issued a non-cited violation for

the noncompliance.

Comanche Peak 1/2 96-10 09/24/96 Narrow None Inspectors observed installation of a penetration seal and no discrepancies were noted.

96-12 11/27/96 Broad None Inspector inspected silicone foam seals and verified that they were installed in the proper

configuration and had adequate documentation to support a 3-hour fire rating.

Cooper 95-17 02/05/96 Narrow None Inspectors closed LER 94-008 regarding inoperable penetration seals.

Crystal River 92-18 10/01/92 Narrow None Inspectors reviewed fire barrier penetration technical specification requirements, including

daily fire barrier breach reports.

97-18 01/06/98 Narrow Minor Inspectors conducted an Appendix R inspection. Inspectors closed restart issues on

penetration seals. Inspectors opened IFI 97-18-01 to track lack of documentation

supporting the seal installations.
Davis-Besse N/A 11/23/94 1 Broad None NRR staff audited the penetration seal program. On the basis of the audit, the staff

concluded that the licensee had implemented and maintained an acceptable fire barrier

penetration seal program and that no significant problems existed with the fire barrier

penetration seal installations. The staff did not find information that suggested problems

with generic implications. 4. .9 .9 .9 .9

Diablo Canyon 1/2 94-01 03/15/94 Broad

Minor

In 1994, the licensee found that certain fire barrier penetration seals may not have met the

required 3-hour fire rating because damming boards were not installed on both sides of

silicone foam seals. A walkdown of additional seals revealed about 100 representative

silicone foam seals with missing damming boards. The licensee has established a

corrective action program. The staff followed up on the licensee's activities during

inspections in February 1994 and March 1995. Inspectors concluded that the licensee had

taken appropriate corrective actions. The staff is continuing to follow the licensee's

actions.

94-07 04/94 Broad None LER 94-01, "Inadequate Fire Barrier Penetration Seals Due to Lack of Damming Boards,"

was closed by inspectors.

94-18 08/15/94 Broad Minor During an inspection of fire barrier penetration seals, inspectors noticed a breached seal.

The breach in the seal was the result of ongoing work and the licensee had appropriate

compensatory measures in place for the breached seal.

95-03 05/01/95 Broad Minor Inspectors reviewed the licensee's corrective actions for LER 94-001, which reported

inadequate silicone foam fire barriers due to lack of damming boards. Inspectors found

that the licensee's actions were appropriate, but the item remained open, as action was still

ongoing.

96-13 08/18/96 Broad None Inspectors closed LER 94-001 concerning inadequate fire barrier penetration seals due to

lack of damming boards. Licensee undertook a 100% inspection of required seals to

document all installed configurations. Inspectors concluded that the licensee's program

would correct the seal deficiencies.

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D.C. Cook 1/2 94-012 06/94 Broad Minor Inspector noted that inoperable fire barrier penetration gap seals were a major problem at

the plant, but the licensee had begun an aggressive program to inspect 485 additional gap

seals.

Duane Arnold 93-012 10/93 Narrow Minor Inspectors described problems licensee was experiencing regarding fire barrier penetration

seals. A major prob!em was noted in this area in an LER in 1992. The licensee was in the

process of a 100% inspection of seals to identify problems.

93-16 10/01/93 Narrow Significant Violation was issued to the licensee based on the lack of action taken regarding degraded

barriers between control room and cable spreading room.

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Farley 1/2 88-27 11/03/88 Narrow Minor Inspectors found several unsealed penetrations during a plant walkdown. These

discrepancies were quickly dispositioned and repaired.

94-30 01/06/95 Narrow None Inspectors reviewed licensee actions regarding notification from a foam seal vendor that

self-extinguish times for a certain lot of RTV foam were out of specification. The licensee

found one penetration seal that was formed of the suspect foam. At the time of the

inspection, the licensee had scheduled to replace the penetration seal.

95-20 01/96 Narrow None The licensee discovered conduit penetrations through a fire barrier without an internal

seal. A broad review of conduit penetrations revealed that there were 125 conduits (3/4"

to 4" diameter) that did not appear to be properly sealed. All conduit inspections and

repairs had been completed and documented.

96-13 12/23/96 Narrow None Inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems With

Fire Barrier Penetration Seals," was appropriate and required corrective actions were

completed.

1.

U,

97-12 09/26/97 Narrow Minor Inspectors reviewed silicone foam penetration seals. Seal documentation did not contain

important design parameters. GL 86-10 evaluations were not available for identified

deviations. IFI 97-12-01 was opened to track these discrepancies.

Fermi 2 94-012 11/23/94 Narrow None As part of a restart inspection, inspectors noted that the licensee had reviewed installation

records, including QA/QC records, for all installed seals and found them indicative of

proper installations. In addition, the licensee had not found any indications of improper

installation upon removal and inspection of several penetration seals.

FitzPatrick 93-12 07/15/93 Broad None Inspectors reviewed licensee special report 93-003 regarding nonfunctional fire barrier

penetration seal. Inspectors concluded that appropriate action was taken to address the

event.

93-14 08/24/93 Broad Minor A seal was opened as part of a plant modification and was not properly restored. The seal

was inoperable for more than 7 days before it was repaired and returned to operability.

Inspectors issued a non-cited violation due to the licensees prompt actions.

93-26 01/04/94 Narrow None As part of a fire protection inspection, penetration seals were inspected.

Ginna 94-14 06/13/94 Broad None Inspector verified that evaluations for existing penetration seal materials supported their

qualification for use throughout the plant. Inspector determined that qualification

documentation for penetration seal materials was concise. Inspector concluded that

controls for maintaining integrity of fire barriers were good and considered this a fire

protection program strength.

Grand Gulf 1 90-10 06/04/90 Narrow Minor Inspectors reviewed an annual fire protection audit, which stated that a number of fire

barrier penetrations that require repair or rework were identified during a walkdown of

Unit 1 rated penetrations.
Haddam Neck 93-08 07/26/93 Narrow None Inspectors closed out LER 93-003, "Fire Barriers Inoperable Due to Fire Seal

Deficiencies." I ~I* 4. 4.

95-09 06/19/95 Broad None Inspector reviewed the fire barrier and penetration seal program to verify the adequacy of

seal installations, qualification, and surveillance activities. Inspector found.that the

licensee conducted a 100 % visual inspection as part of its seal upgrade program in 1988.

Licensee found 20 degraded or inoperable seals since the upgrade program. Inspector

concluded that the licensee took prompt and appropriate corrective actions. On the basis

of the inspection, inspector concluded that no safety concerns exist at the facility

regarding fire barriers. 4. 6 4. 4. 4

Hatch 1/2 88-21 08/23/88 Narrow None Inspectors reviewed the licensee's actions taken in response to IN 88-04, "Inadequate

Qualification and Documentation of Fire Barrier Penetration Seals." Inspectors concluded

that the licensee had planned to implement an adequate action plan, and that the

implementation would be the subject of a future inspection.

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V~

91-30 12/19/91 Narrow None Inspectors noted that penetration seals were acceptable during a general plant walkdown.

92-09 04/20/92 Narrow None Inspectors noted that penetration seals were acceptable during a general plant walkdown.

93-22 11/2/93 Narrow None Inspectors noted that penetration seals were acceptable during a general plant walkdown.

97-01 03/24/97 Narrow None Inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems With

Fire Barrier Penetration Seals," was appropriate and required corrective actions were

completed.

97-03 6/17/97 Broad None Inspectors reviewed procedures, drawings, and other documents related to fire-rated

sealed penetrations and conducted walkdowns of selected sealed penetrations. Inspectors

concluded that the licensee's program for determining the operability of sealed

penetrations was adequate. No deficiencies were identified with the penetrations

inspected.

98-01 04/21/98 Broad Minor Inspectors reviewed several fire barrier penetration seals, including supporting

documentation. A visual inspection did not reveal any discrepancies. Inspectors opened

IFM 98-01-05 to track issues related to fire test documentation that was unavailable at the

time of the inspection.

Indian Point 2 93-18 09/13/93 Broad None Inspectors reviewed the licensee's fire barrier penetration seal installation and surveillance

program and the licensee's actions in response to IN 88-04. No discrepancies were found.

The licensee does not use silicone foam-type penetration seals. Grout seals are utilized.

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Indian Point 3 93-24 12/14/93 Broad Minor Inspectors opened URI.93-24-03, which concerned operability determinations of degraded

and potentially nonconforming fire barriers and fire barrier penetration seals and the

methodology that the licensee used to determine self-ignition temperatures of cables

installed in penetrations in the plant. The latter issue has yet to be resolved.

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03

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93-80 06/21/93 Narrow Minor Inspectors identified weaknesses in programs dealing with fire barrier penetration seals.

Specifically licensee commitments to revise technical specifications to add fire barrier

penetrations needed to meet Section III.G of Appendix R.

95-10 06/26/95 Narrow Minor Inspectors questioned the methodology used by the licensee to determine the self-ignition

temperature of cables that pass through penetration seals. However, inspectors had found

the licensee's penetration seal analyses and supporting documentation to be generally

sufficient. The NRC is currently tracking corrective actions at IP3.

95-81 05/11/95 Narrow Minor Inspectors reviewed fire barrier penetration seal qualification tests and concluded that

insufficient evidence was available to support the cable ignition temperatures of cables

installed at IP3. (Similar to preceding summary.)

Kewaunee 96-004 06/05/96 Broad Minor Inspector cited the licensee for a lack of corrective action in restoring a degraded fire

barrier penetration seal that was identified as impaired, but not dispositioned or repaired.

There were no compensatory measures taken for this degraded fire barrier. The licensee

was issued a Level IV violation.

LaSalle 96-04 07/03/96 Narrow Broad Inspectors noted that barrier seals in the plant were in generally good condition.

Maine Yankee 95-15 09/20/95 Broad None Inspector reviewed the fire barrier program to verify the adequacy of penetration seal

installations, qualification, and inspection activities. Inspector concluded that the

licensee's procedures for seal inspections and training provided to seal inspectors were

good for maintaining proper seal configuration and early detection of degraded

conditions.

96-08 09/16/96 Broad Significant Inspectors reviewed actions taken by the licensee to address problems identified with

penetration seals. Inspectors concluded that the licensee took prompt and effective actions

to address these problems.

97-03 06/05/97 Broad Minor Inspectors reviewed the licensee's activities involving the fire barrier penetration seal

repair project. 90% of the 2600 seals inspected were determined to require repair or

replacement.

89-03 04/06/89 Narrow None Inspectors reviewed the licensee's actions in response to IN 88-04 and found that they

McGuire 1/2 were adequate to address the concerns outlined in the IN.

92-01 02/19/92 Narrow None Inspectors noted that penetration seals were acceptable during a general plant walkdown.

98-07 08/04/98 Broad None Inspectors reviewed licensee's fire barrier penetration seal program and concluded that

seal designs were properly supported by seal testing documentation, vendor data, design

data and inspection.
Millstone 1/3

Millstone 2

93-19,

93-14,

93-15

10/06/93 Narrow None Inspectors reviewed licensee corrective actions for LER 93-06. 100% inspections are

done every 18 months for Unit 1. Inspectors reviewed revised penetration seal

surveillance procedure and found it adequate. Overall, the corrective actions were

appropriate.

Monticello 92-007 04/10/92 Narrow None Inspector observed fire penetration seals while conducting a plant walkdown and did not

observe problems.

93-005 04/93 Narrow None Inspectors closed LER 91-21, which reported inoperable fire barrier penetration seals due

to pipe movement caused by a water hammer. Inspectors felt the actions taken by the

licensee to resolve this problem were adequate.

North Anna 1 88-13 09/13/88 Narrow None Inspectors reviewed several exemptions requests and inspected penetration seals including

North Anna 2 supporting documentation. Inspectors did not identify any discrepancies.

92-18 10/19/92 Broad Significant Inspectors identified several degraded penetration seals and upon review of the

penetration seal program found deficiencies in procedures and documentation. Two

violations were issued for failure to maintain penetration fire barriers (92-18-04) and

failure to establish adequate fire barrier inspection procedure (92-18-05).

93-13 03/30/93 Narrow None During a general plant walkdown, inspectors noted that penetration seals were acceptable.

93-20 09/17/93 Broad Minor Inspectors observed penetration seal inspections where removal of marinite damming

boards revealed gaps in penetration seal underneath. The same problems were found in 5

other seals. Fire watches were put into place until the inspections and repair were

completed.

94-10 06/09/94 Narrow None Inspectors reviewed licensee's corrective actions for violations 92-18-04 and 92-18-05.

Violation 92-18-04 remained open, pending licensee's review of penetration seal

inspection schedule. Violation 92-18-05 was closed.

94-15 08/02/94 Broad None Inspectors reviewed the licensee's results from penetration seal inspections. Based on the

conclusions of the inspections, Inspector closed violation 92-18-04.

96-13 02/07/97 Broad None In 1995, the licensee initiated destructive inspections of penetration seals. It found and

repaired a number of degraded seals. On the basis of this inspection, inspectors concluded

that the licensee's corrective action program was very effective.

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Oconee 1/2/3 88-19 07/21/88 Broad None Inspectors closed LER 88-05 on inoperable fire barrier penetration seals based on their

review of the licensee's corrective actions.

91-14 08/01/91 Narrow None Inspectors reviewed the licensee's procedure for 18-month surveillance of fire barrier

penetration seals. They also inspected seals during a plant walkdown and noted no

discrepancies.

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97-15 12/15/97 Broad Minor Inspectors reviewed the licensee's penetration seal program. The licensee had initiated a

reverification program for penetration seals in all 3 units. Inspectors opened IFI 97-15-07

to follow this effort.

Oyster Creek 93-10 06/21/93 Broad None Inspectors viewed penetration seals during plant walkdown. No visible discrepancies

were noted. Inspectors also reviewed licensee actions in response to IN 88-56. Licensee

conducted inspections of installed silicone foam quality during installation and at periodic

intervals by removing damming boards.

95-11 07/21/95 Broad Minor Inspection was conducted because licensee reported finding degraded penetration seals

(125 of about 1560 seals) during its 18-month seal inspection program. Inspector

concluded that the licensee had accurately identified, evaluated, and initiated proper

compensatory and/or repair activities. Inspector concluded that there were no outstanding

operability or functionality issues.

Palisades 92-010 03/92 Narrow None Inspector reviewed licensee's fire barrier penetration surveillance procedure. No

discrepancies were noted.

Palo Verde 1/2/3 94-29 09/02/94 Broad None Inspector reviewed the licensee's fire barrier seal program and found that extensive

inspections had been completed and deficiencies were being addressed by the licensee.

Peach Bottom 2/3 93-09 05/14/93 Broad Minor Inspectors reviewed the licensee's fire barrier penetration seal installation and surveillance

program. Voids were discovered in some silicone foam penetration seals. The licensee

responded by inspecting all seals supported by a given detail. Inspectors concluded that

the licensee's penetration repair program appeared to be an adequate approach for

identifying and correcting nonconforming penetrations.

Perry 1 96-016 02/04/97 Narrow Minor Inspector opened an unresolved item regarding penetration seals that were installed in a

different configuration from the supporting tested assembly. The licensee was to

complete an engineering evaluation.

Pilgrim 1 92-27 12/30/92 Narrow None During a fire protection inspection, while on a plant tour, inspectors inspected penetration

seals. No adverse conditions were noted.

97-03 07/22/97 Broad Minor Inspector discovered a penetration seal with a small void at the top of the seal. The seal was determined to be degraded but operable. The seal was to be repaired.

Prairie Island 1/2 92-010 08/14/92 Narrow None Seals for separation of diesel generators from other plant areas were inspected and verified

as 3-hour rated.
River Bend Station 94-17 01/17/95 Narrow None Inspection team observed penetration seals during a fire protection-related plant tour. No

discrepancies were noted.

94-22 01/26/95 Narrow None Inspectors questioned the radiation shielding capability of Kaowool installed as a

penetration seal. The licensee was able to adequately justify the application.

95-01 03/08/95 Narrow Minor Inspectors found that inadequate corrective actions for misapplication of seal material in

1991 caused seals to degraded by high ambient temperatures. Inspectors opened URI 95-

01-02.

95-02 05/03/95 Narrow Minor Inspector follow-up on URI 95-01-02 concluded that the licensee was acting

appropriately, but more work was needed to resolve the problems.

95-17 06/09/95 Narrow Minor

LA

LA

CA

The licensee received a non-cited violation for failure to promptly identify and correct the

inadequate design of the boot seal that had degraded. Inspectors closed URI 95-01-02,

based on the licensee's ongoing efforts to correct the seal problem. I 1 1. 4.

H.B. Robinson 2 88-31 01/12/89 Narrow Minor Inspectors generated IFI 88-31-01 based on their review of GL 86-10 evaluations of seals

that did not meet the technical specification surveillance acceptance criteria. Seals were

dispositioned in engineering evaluations rather than being repaired.

90-15 08/06&•0 Narrow None Inspectors reviewed the licensee's fire barrier inspection project, which was initiated to

ensure that all seals were operable per plant technical specifications. IFI 88-31-01

remained open pending the completion of this project.

91-13 05/17/91 Narrow None Inspectors closed LER 90-10 on an inoperable penetration seal, and IFI 88-31-01 based on

the completion of the licensee's penetration seal inspection project. Several seals were

scheduled to be repaired because of the inspection project.

96-12 12/16/96 Narrow None Inspectors noted that penetration seals were adequate during a general plant walkdown.

Also, inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems

With Fire Barrier Penetration Seals," was appropriate and required corrective actions were

completed.

-4

0

0

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U'
St Lucie 1 96-08 07/08/96 Narrow None Inspectors evaluated the licensee's actions to resolve fire protection discrepancies during

St. Lucie 2 the 1996 Unit 1 refuelihg outage. The licensee had inspected penetration seals and found

P small cracks in the surfaces of the seals. Inspectors concluded that the discrepancies did

not appear to degrade the fire resistance of the seals. However, the licensee considers

seals with even cosmetic problems to be inoperable. Inspectors found that the licensee's

.. corrective actions and compensatory measures were appropriate.

97-06 08/25/97 Broad Minor Inspectors cited licensee for failure to promptly take appropriate corrective actions to

resolve mechanical penetration seal deficiencies.

Salem 1 93-80 10/14/93 Narrow None Inspectors reviewed results of 18-month fire barrier penetration seal surveillance

Salem 2 conducted by the licensee. No discrepancies were noted.

96-01 03/25/96 Broad None Inspectors reviewed the licensee's procedure for fire barrier penetration seal inspections.

96-10 10/30/96 Broad None This issue was a restart action plan item. Inspectors reviewed work done during the

penetration seal improvement program and concluded that the quality and configuration of

penetration seals were acceptable.

1 4

N 97-09 06/03/97 Broad None Inspectors reviewed the qualification-type fire endurance tests and associated engineering oevaluations for certain seal designs in floors and walls in Unit 1 and Unit 2 auxiliary

buildings. Inspectors focused on verifying that design and installation parameters for the

as-built configurations were bounded and justified by the licensee's engineering

evaluations. Inspectors concluded that the licensee's engineering analysis methods

appeared to have established a basis that the as-built seal designs would accomplish their

intended function.

San Onofre 2/3 94-01 01/28/94 Broad None The licensee conducted a 100 % reverification program of the installed configurations as a

part of the validation of the Plant and Equipment Data Management System database.

The licensee found that 4 of 1500 seals (a 20 % sample of a total of 7000 seals) did not

meet acceptance criteria. (The reverification process was ongoing at the time of the

inspection.) Inspector walked down and verified the adequacy of a sample of installed

seals. Inspector did not report any safety-significant problems.
Sequoyah 1/2 88-54 01/13/89 Narrow Minor Inspectors reviewed procedures for licensee penetration seal inspections. Inspectors also

found 2 fire barrier penetration seals that were breached by a rubber hose. Inspectors

opened IFI 88-54-05.

92-14 06/05/92 Broad Minor Inspectors closed LERs 91-010, 91-008, 91-016, and 91-012. Licensee had planned a

100% inspection and reverification of all installed seals in accordance with IN 88-04.

94-16 07/19/94 Broad None Inspectors reviewed the licensee's response to IN 88-04, which included inspection and

seal re-work. Inspectors concluded that the licensee's followup on the IN was adequate.

96-02 04/22/96 Broad Minor Inspectors reviewed a 1994 licensee audit in which items identified included inadequate

design control over fire barrier penetration seals and restoration of pen seals to operability

following maintenance. Corrective actions on these items were incomplete at the time of

the inspection.

96-10 09/27/96 Broad Minor Inspectors reported that a 100% seal inspection had been completed (24,500 seals

inspected) and 1500 seals with design documentation problems remained to be resolved.

Scheduled for completion late 1997.

97-03 05/12/97 Narrow None Inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems With

Fire Barrier Penetration Seals," was appropriate and required corrective actions were

completed.

98-07 08/07/98 Broad Minor Inspectors reviewed licensee's penetration seal program, including a walkdown of 24

silicone foam penetration seals. Inspectors opened IFI 97-08-10 to track licensee's actions

concerning the evaluation of installed seal configurations that are not adequately

supported by a fire test.

z

C1.

Shearon Harris 95-02 03/02/95 Narrow None Inspectors observed penetration seal 18-month visual inspection conducted by licensee

personnel. Performance of the inspection was found to be satisfactory.

98-01 03/27/98 Broad Minor Inspectors reviewed the licensee's penetration seal program. 3 of the seals inspected

lacked adequate supporting documentation and engineering analysis. A violation was

cited based on this weakness

South Texas 1/2 94-15 06/07/94 Narrow Minor IFI regarding excessive shrinkage of penetration seals was closed in the report.

95-01 03/06/95 Narrow None Inspector visually inspected penetration seals in various fire areas and found no

discrepancies.

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C) Sorry 1/2 88-07 03/17/88 Narrow None During a fire protection inspection, inspectors reviewed procedures for the licensee's fire

stop and fire retardant coatings surveillances. 0

0•

05

93-18 07/27/93 Narrow None During (A a fire protection inspection, inspectors reviewed procedures for the licensee's fire

_I I I I stop and fire retardant coatings surveillances.

96-10 10/28/96 Narrow None Inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems With

Fire Barrier Penetration Seals," was appropriateand required corrective actions were

completed. t I -f

Susquehanna 1 95-12 08/02/95 Narrow Minor Inspectors followed up on LERs 94-003 and 94-007 for a missing seal and a degraded

seal. Both discrepancies were corrected.

95-14 07/31/95 Broad None Inspector conducted a comprehensive inspection of the licensee's penetration seal program

including, reviewing the adequacy of the penetration seal installations, qualification, and

inspection activities. Inspector also assessed the appropriateness of acceptance criteria for

validating operability and degradation. Inspector concluded that the licensee had an

excellent program.

96-201 04/05/96 Broad Minor NRR staff inspected the fire barrier penetration seal program and found the damming

material missing from one penetration seal. The licensee took immediate corrective

actions. Inspectors concluded that the licensee had implemented and maintained an

acceptable fire barrier penetration seal program. Inspectors did not find safety-significant

problems or evidence of generic problems with penetration seals. 4 4 4.

Turkey Point 3/4 88-37 01/05/89 Narrow Minor During a fire protection inspection, inspector reviewed the procedure for penetration fire

barrier surveillances. Inspector noted that the procedure did not identify that all the

installed fire barriers met Appendix R requirements. The procedure was being revised at

the time of the inspection.

92-23 10/29/92 Narrow None During a fire protection inspection, inspector reviewed the penetration seal inspection

procedure. Inspector noted no discrepancies in penetration seals during a plant walkdown.

96-06 06/03/96 Narrow Minor Licensee QA audits of fire protection program were reviewed. Findings regarding

penetration seal documentation were identified. Corrective actions were determined to be

adequate.

97-11 11/24/97 Broad Minor Inspectors reviewed the licensee's actions in response to INs 88-04, 88-56, and 94-28. The

licensee was evaluating the adequacy of silicone elastomer seals and found some seals

without supporting documentation. Inspectors opened IFI 97-11-04 to track the licensee's

progress in evaluating all the seals installed at the plant.
Vermont Yankee 93-05 05/13/93 Broad Significant A violation was issued to the licensee for inadequate application of quality principles to

the original installation and the subsequent ineffective periodic inspections of the fire

barrier penetration seals installed in the reactor building, control building, and diesel

generator rooms.

Virgil C. Summer 96-11 11/25/96 Narrow None Inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems with Fire

Barrier Penetration Seals," was appropriate and required corrective actions were

completed.

Vogtle 1/2 88-24 06/29/88 Narrow Minor Following a spurious actuation of a fire suppression system, several fire penetration seals

allowed the passage of water from one fire area to another. Inspector issued a Level IV

violation for the failure to adequately design and install watertight penetration seals.

91-10 06/13/91 Narrow Minor During a fire protection inspection, inspector (during a walkdown), found an unsealed

penetration. Inspector issued a Level IV violation for this and other fire protection

deficiencies.

92-13 08/04/92 Broad None Inspectors completed an inspection on fire barrier penetration seals. Inspectors reviewed

surveillances, noted discrepancies, and confirmed that all deficiencies were corrected.

There were no findings in this area.

93-08 05/17/93 Narrow None Inspectors found penetration seals to be adequate during a general plant walkdown.

Violation 91-10-01, concerning corrective actions for missing penetration seals, was

closed.

95-31 02196 Narrow None Inspectors closed LER 95-01 for lack of penetration seals placing plant in condition

outside of design basis. Corrective actions were found to be adequate.

97-01 04/14/97 Narrow None Inspectors concluded that licensee's evaluation of IN 94-28, "Potential Problems With

Fire Barrier Penetration Seals," was appropriate and required corrective actions were

completed.

97-12 02/23/98 Broad None Inspectors reviewed the licensee's fire barrier penetration seals program, which included

the inspection of individual penetration seals. Inspectors concluded that seal designs were

properly supported by testing documentation, vendor data, installer qualification and

training records, and quality assurance inspection records.

I

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Washington Nuclear 2 94-08 02/25/94 1 Broad Minor In December 1993, the licensee began a review of issues related to its penetration seal

inspection program. The licensee found deficiencies with original installations, periodic

inspections, and repairs. The licensee declared all seals inoperable, established

compensatory measures, and initiated a comprehensive penetration seal upgrade program.

NRC Region IV conducted three inspections of the program. Inspectors concluded that

the licensee was taking aggressive corrective actions.

CD

94-09 05/04/94 Broad None SALP report noted that penetration seal problems were not properly addressed by the

licensee until the NRC became involved.

94-28 11/09/94 Broad Significant The staff issued a violation (94-28-01) for not taking prompt compensatory measures

upon the discovery of installation' and inspection deficiencies for fire barrier penetration

seals. Inspectors viewed approximately 100 penetration seals and noted that many had

small cracks or gaps along the seal-wall interface. Inspectors did not believe that the

deficiencies made the barriers nonfunctional.

95-18 06/29/95 Broad None Inspectorsclosed violation 94-28-01. The licensee had completely restructured its fire

protection program, including its penetration seal program.

95-201 10/03/95 Broad None An NRC integrated assessment team inspected the licensee activities mentioned in the

previous inspection reports. The team assessed licensee effectiveness in identifying

issues, performing root cause analyses, and implementing corrective actions. The

inspection focused on the areas of maintenance and engineering. The team inspected

activities involving procurement, storage, installation, quality control, and long-term

maintenance associated with the installation and maintenance of penetration seals. The

team concluded that the licensee's current performance in the areas of receipt inspection

and storage control, quality control, and inspection and surveillance was adequate. The

assessment team also considered the licensee's corrective action program on penetration

seals to be a strength.

Waterford 3 N/A 10/07/94 Broad None NRR staff audited the penetration seal program. The staff found several minor

weaknesses with fire test results and training records. The staff concluded, however, that

the fire barrier penetration seal program was satisfactory and that the discrepancies did not

create any problems with the penetration seal installations. The staff did not find safetysignificant problems or evidence to suggest that generic problems existed with penetration

seals.

95-11 02/16/95 Narrow None Inspector visually inspected penetration seals in various fire areas. No discrepancies were

identified. Fire barrier penetration seal program implementing procedure was also

reviewed.
Watts Bar I 94-62 11/16/94 Narrow Minor Inspectors opened construction deficiency reports (CDRs) 85-18/19 and 90-10 for firerated penetration deficiencies and unqualified cable penetration seals. These issues were

inspected several times over a 2-year period.

94-78 12/21/94 Broad None Inspectors reviewed penetrations and supporting documentation for a number of seals. In

addition, inspectors observed several seal installations. Inspectors concluded that an

effective program was being implemented for the evaluation of existing electrical and

mechanical fire barrier penetration seals and the repair, modification, and installation of

penetration seals to meet design requirements.

95-32 06/09/95 Narrow None Inspectors continued followup on CDR 85-19.

95-38 07/11/95 Narrow Minor Inspectors discovered degraded penetration seals during a plant tour.

95-39 07/18/95 Narrow None Inspectors closed CDR 87-13, which concerned deficiencies with mechanical fire

protection penetration seals.

95-40 09/12/95 Narrow Minor Documentation of the fire testing for fire barrier penetration seals did not conform to the

design details for some installed seals. This follows from previous CDRs.

95-45 08/15/95 Narrow Minor Inspector noted that a penetration seal had been breached.

95-68 10/19/95 Broad None Inspectors reviewed design details and QA/QC records, and walked down penetration

seals. No discrepancies were identified for the seals that were reviewed. During the

walkdown some seals were noticed to have damaged damming boards. The applicant was

already aware of these deficiencies.

95-72 11/17/95 Narrow None Inspectors closed CDR 85-19 for penetration assembly deficiencies.

95-77 12/06/95 Narrow None Inspectors closed second CDR (90-10) for unqualified penetration seals.

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Wolf Creek 94-02 04/15/94 Broad Minor Cracks found in fire barrier material which formed a penetration seal between two areas.

95-19 08/10/95 Narrow None Inspector visually inspected penetration seals in various fire areas. No discrepancies were

I _identified. C,,

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Appendix J

Plants Known To Have Performed

100-Percent Penetration Seal Inspections

Arkansas Nuclear One 1 1974 LER 91-016.

Arkansas Nuclear One 2 1980 LER 91-016

Big Rock Point 1963 LERs 89-006 and 91-001.

Browns Ferry 2/3 1975/1977 NRC IR 98-01.

Brunswick 1/2 1977/1975 LER 93-006-00.

Calvert Cliffs 1/2 1975/1977 NRC IR 94-15.

Catawba 1/2 1985/1986 McGuire LER 88-030-01.

D.C. Cook 1/2 1975/1978 LER 96-004-00.

Diablo Canyon 1/2 1985/1986 LER 94-001-00. NRC IRs 94-01 and 95-03.

Duane Arnold 1975 NRC JR 93-012.

FitzPatrick 1975 LER 91-024-01.

Fort Calhoun 1973 LER 90-022.

Haddam Neck 1968 LERs 89-001-00 and 95-001-00. NRC IR 95-09.

Indian Point 3 1976 NRC JR 95-8 1.

McGuire 1/2 1981/1984 LER 88-030-01.

Maine Yankee 1973 LER 96-017-00. NRC IR 96-08.

Millstone 1 1986 LER 93-006-01, NRC IR 93-19.

Monticello 1971 LER 89-001-00.

Nine Mile Point 1 1969 LER 88-009-00.

Oconee 1/2/3 1973/1973/1974 LERs 89-010-03 and 88-005, NRC IR 97-15.

Palo Verde 1/2/3 1986/1986/1988 Letter of March 16, 1990.

River Bend Station 1986 LER 89-010-03.

H.B. Robinson 2 1971 LER 91-010-01.

Salem 1 1977 LER 88-013-00.

Salem 2 1981 LER 88-013-00.

COMM. OP. = Date of Commercial Operation, LER = Licensee Event Report, NRC IR = NRC Inspection Report

J-1 NUREG-1552, Supp. 1
100% Penetration Seal Inspection

San Onofre 2/3 1982/1983 NRC IR 94-01.

Susquehanna 1 1983 NRC IR 95-12.

Sequoyahl/2 1981/1982 NRC IR 96-10.

Vermont Yankee 1972 LER 93-001.

Washington Nuclear 2 1984 LER 88-008-00. NRC IRs 94-08, 94-28, 95-18, and 95-201.

Watts Bar 1 1996 NRC IR 95-77.

NUREG-1552, Supp. 1 J-2
Appendix K

Reference Summary

Arkansas Nuclear One 1 1974 LERs 89-003-00,90-004-00,90-04-01, 90-004-02,

90-017-00, and 90-023-00.

Arkansas Nuclear One 2 1980 LERs 87-001-00 and 91-016-00.

Beaver Valley 1 1976 NRC IRs 93-12 and 93-13.

Beaver Valley 2 1987 NRC IRs 93-12 and 93-13.

Big Rock Point 1963 LERs 89-006-00, 89-006-01, 91-001-00, and 91-001-01.

Braidwood 1/2 1988/1988 N/A.

Browns Ferry 1/2/3 1974/1975/1977 NRC IRs 89-28, 90-11, 92-11, 95-60, and 98-01.

Brunswick 1/2 1977/1975 LER 93-006-00; NRC IRs 92-31, 93-08, 93-38, 97-07, and

97-13.

Byron 1/2 1985/1987 NRC IR 92-007.

Callaway 1984 NRC IR 94-12.

Calvert Cliffs 1/2 1975/1977 LERs 89-002-00, 89-002-01, and 95-004-00;

NRC IRs 94-15, 93-99, 95-08, and 96-201.

Catawba 1/2 1985/1986 McGuire LER 88-030-01; NRC IRs 91-22, 97-07, and 98-07.

Clinton 1987 LERs 89-006-00 and 98-021-00.

Comanche Peak 1/2 1990/1993 NRC Ills 96-10 and 96-12.

Cooper 1974 LER 94-008-00; NRC IR 95-17.

Crystal River 3 1977 NRC IRs 92-18 and 97-18.

Davis-Besse 1978 1994 NRR audit.

D.C. Cook 1/2 1975/1978 LER 96-004-00; NRC IR 94-012.

Diablo Canyon 1/2 1985/1986 LERs 94-001-00, 94-001-01, 96-011-00, and 96-011-01;

NRC IRs 94-01, 94-07, 94-18, 95-03, and 96-13.

Dresden 2/3 1970/1971 LER 89-030-00.

Duane Arnold 1975 LERs 92-003-00, 92-007-00, and 92-007-01;

NRC IRs 93-012 and 93-16.

Farley 1 1977 NRC IRs 88-27, 94-30, 95-20, 96-13, and 97-12.

Farley 2 1981 NRC IRs 88-27, 94-30, 95-20, 96-13, and 97-12.

COMM. OP. = Date of Commercial Operation, LER = License Event Report, NRC IR = NRC Inspection Report

K-1 NUREG-1552, Supp. 1
Reference Summary

Fermi 2 1988 LERs 97-014-00 and 97-014-01; NRC IR 94-012.

FitzPatrick 1975 LERs 87-011-00, 87-011-01, 91-024-00, and 91-024-01;

NRC IRs 93-12, 93-14, and 93-26.

Fort Calhoun 1973 LERs 90-022-00, 90-022-01, and 90-022-02.

Fort St. Vrain LERs 87-006-00. 87-006-01, 89-014-00, and 89-014-01.

Ginna 1970 LER 88-009-00; NRC IR 94-14.

Grand Gulf 1 1985 NRC IR 90-10.

Haddam Neck 1968 LERs 89-001-00, 89-001-01, 92-008-00, 93-003-00,

95-001-00, and 95-001-01; NRC IRs 93-08 and 95-09.

Hatch 1 1975 NRC IRs 88-21, 91-30, 92-09, 93-22, 97-01, 97-03, and

98-01.

Hatch 2 1979 NRC IRs 88-21, 91-30, 92-09, 93-22, 97-01, 97-03, and

98-01.

Hope Creek 1 1986 N/A.

Indian Point 2 1974 NRC IR 93-18.

Indian Point 3 1976 LER 93-029-00; NRC IRs 93-24, 93-80, 95-10, and 95-81.

Kewaunee 1974 NRC IR 96-004.

LaSalle 1/2 1984/1984 LER 93-009-00; NRC IR 96-04.

Limerick 1/2 1986/1990 N/A.

Maine Yankee 1973 LERs 94-010-00, 94-010-01, 96-017-00 and 97-017-01;

NRC IRs 95-15 and 96-08.

McGuire 1/2 1981/1984 LERs 88-030-00 and 88-030-01; NRC IRs 89-03, 92-01,

97-03, and 98-07.

Millstone 1 1986 LERs 93-006-00 and 93-006-01; NRC IR 93-19.

Millstone 2 1975 LER 94-035-00; NRC IR 93-14.

Millstone 3 1986 NRC IR 93-15.

Monticello 1971 LERs 87-011-00, 89-001-00, 89-013-00, 89-013-01,

90-009-00, and 91-021-00; NRC IRs 92-007 and 93-005.

Nine Mile Point 1 1969 LERs 88-009-00, 88-009-01, and 88-009-02.

Nine Mile Point 2 1988 LERs 87-016-00, 87-016-01, and 87-018-00

North Anna 1 1978 LERs 88-007-00 and 89-003-00; NRC IRs 88-13, 92-18,

93-13, 93-20, 94-10, 94-15, and 96-13.

North Anna 2 1980 LERs 88-007-00 and 89-003-00; NRC IRs 88-13, 92-18,

1_ 1 93-13, 93-20, 94-10, 94-15, and 96-13.

NUREG-1552, Supp. 1 K-2
Reference Summary

Oconee 1/2/3 1973/1974/1974 LERs 88-005-00 and 89-010-03; NRC IRs 88-19, 91-14, and

97-15.

Oyster Creek 1969 NRC IRs 93-10 and 95-11.

Palisades 1971 LERs 89-024-00 and 96-009-00; NRC IR 92-010.

Palo Verde 1/2/3 1986/1986/1988 LERs 90-009-00 and 90-009-01; NRC IR 94-29

Peach Bottom 2/3 1974/1974 LER 91-013-00; NRC IR 93-09.

Perry 1 1987 NRC IR 96-06.

Pilgrim 1 1972 NRC IRs 92-27 and 97-03.

Point Beach 1/2 1970/1972 LER 91-007-00.

Prairie Island 1/2 1973/1974 LER 98-003-00; NRC IR 92-010.

Quad Cities 1/2 1973/1973 LER 87-028-00

River Bend Station 1986 LERs 87-021-00, 88-009-00, 88-009-01, 88-009-02,

89-005-00, 89-010-00, 89-010-01, 89-010-02, 89-010-03,

89-010-04, and 89-010-05; NRC IRs 94-17, 94-22, 95-01,

95-02, and 95-17.

H.B. Robinson 2 1971 LERs 88-018-00, 88-018-01, 90-003-00, 90-008-00,

90-010-00, 90-010-01, and 91-010-01; NRC IRs 88-31,

90-15, 91-13, and 96-12.

St. Lucie 1 1976 LERs 97-004-00 and 97-008-00; NRC IRs 96-08 and 97-06.

St. Lucie 2 1983 LERs 97-004-00 and 97-008-00; NRC IRs 96-08 and 97-06.

Salem 1 1977 LERs 87-007-00, 88-013-00, and 88-014-00; NRC IRs 93-80,

96-01, 96- 10, and 97-09.

Salem 2 1981 LERs 87-007-00, 88-013-00, and 88-014-Qg; NRC IRs 93-80,

96-01, 96-10, and 97-09.

San Onofre 2/3 1983/1984 NRC IR 94-01.

Seabrook 1 1990 LERs 89-011-00 and 89-011-01

Sequoyah 1/2 1981/1982 LERs 91-013-00, 91-013-01, 91-016-00, and 91-016-01;

NRC IRs 88-54, 92-14, 94-16, 96-02, 96-10, 97-03, and

98-07.

Shearon Harris 1987 NRC IRs 95-02 and 98-01.

South Texas 1/2 1988/1989 NRC IRs 94-15 and 95-01.

Susquehanna 1 1983 LERs 87-011-00, 89-019-00, and 95-011-00; NRC IRs 95-12,

95-14, and 96-201.

Summer 1984 NRC IR 96-11.

Surry 1/2 1972/1973 NRC IRs 88-07, 93-18, and 96-10.

K-3 NUREG-1552, Supp. 1
Reference Summary

Three Mile Island 1 1974 LER 87-003-00

Trojan LERs 90-022-00, 90-022-01, 92-006-00, 92-006-01,

92-011-00, 92-026-00, 92-026-01, 92-026-02, 92-026-03,

92-026-04, 92-026-05; 92-031-00; 92-034-00, 93-001-00, and

93-002-00.

Turkey Point 3/4 1972/1973 NRC IRs 88-37, 92-23, 96-06, and 97-11.

Vermont Yankee 1972 LERs 93-001-00, 93-001-01, 93-001-02, 94-018-00,

94-018-01, 95-004-00, 96-026-00, 96-026-01, 98-001-00, 98-

001-01, 98-008-00, 98-008-01, 98-014-00, 98-014-01; NRC

IR 93-05.

Vogtle 1/2 1987/1989 NRC IRs 88-24, 91-10, 92-13, 93-08, 95-31, 97-01, and

97-12.

Washington Nuclear 2 1984 LERs 87-004-00, 87-029-00, 87-030-00, 88-008-00,

88-008-01, 94-002-00, and 94-002-01; NRC IRs 94-08,

94-09, 94-28, 95-18, and 95-201.

Waterford 3 1985 LERs 88-011-00, 88-025-00, 88-030-00, 88-030-01,

88-030-02, 88-030-03, 90-019-00, 90-019-01, and

90-019-02; NRC IR 95-11 and 1994 NRR audit.

Watts Bar 1 1996 NRC IRs 94-62, 94-78, 95-32, 95-38, 95-39, 95-40, 95-45,

95-68, 95-72, and 95-77.

Wolf Creek 1 1985 LERs 87-001-00, 87-010-00, 87-010-01, and 87-010-02;

NRC IRs 94-02 and 95-19.

Zion 1/2 1973/1974 N/A.

NUREG-1552, Supp. 1 K-4
NRC FORM 335 U.S. NUCLEAR REGULATORY COMMISSION 1. REPORT NUMBER

(2-89) (Assigned by NRC, Add Vol., Supp.,

NRCM 1102, Rev., and Addendum Numbers, if any.)

3201,3202 BIBLIOGRAPHIC DATA SHEET

(See instructions on the reverse) NUREG- 1552, Supplement 1

2. TITLE AND SUBTITLE

3. DATE REPORT PUBLISHED

Fire Barrier Penetration Seals in Nuclear Power Plants MONTH I YEAR

January 1999

4. FIN OR GRANT NUMBER

5. AUTHOR(S) 6. TYPE OF REPORT

Technical

C. S. Bajwa and K. S. West 7. PERIOD COVERED (Inclusive Dates)

8. PERFORMING ORGANIZATION - NAME AND ADDRESS (If NRC, provide Division, Office or Region, U.S. Nuclear Regulatory Commission, and mailing address; if contractor,

provide name and mailing address.)

Division of Systems Safety Analysis

Office of Nuclear Reactor Regulation

U.S. Nuclear Regulatory Commission

Washington, DC 20555-0001

9. SPONSORING ORGANIZATION - NAME AND ADDRESS (If NRC, type "Same as above": if contractor, provide NRC Division, Office or Region, U.S, Nuclear Regulatory Commission,

and mailing address.)

Same as above

10. SUPPLEMENTARY NOTES

11. ABSTRACT (200 words or less)

Nuclear power plants use the "defense in depth" concept of echelons of fire protection to achieve a high degree of

fire safety. The objective of this concept is to (1) prevent fires from starting; (2) rapidly detect, control, and

extinguish those fires that do occur; and (3) protect structures, systems, and components important to safety so that

a fire that is not promptly extinguished will not prevent the safe shutdown of the plant. Fire barrier penetration

seals, which are but one part of one element of the fire protection defense-in-depth concept, are designed to

maintain the fire rating of a barrier where penetrating items pass through the barrier. This is essential if the barrier

is to confine a fire to the area in which it started or to protect plant systems and components within an area from a

fire outside the area. On the basis of everything it found and considered, it is the staff's judgment that, overall, the

issue of potential fire barrier penetration seal deficiencies does not affect safety. For the reasons given in this

paper, typical penetration seal deficiencies do not necessarily equate to a lack of adequate protection or result in

undue risk to public health and safety. It is the staff's opinion that continued licensee upkeep of existing

penetration seal programs and continued NRC inspections are adequate (1) to ensure that penetration seal

problems are discovered and resolved and (2) to maintain public health and safety.

12. KEY WORDS/DESCRIPTORS (List words or phrases that will assist researchers in locating the report.) 13. AVAILABIUTY STATEMENT

Unlimited

14. SECURITY CLASSIFICATION

Fire Barrier Penetration Seals (This Page)

Silicone Foam Unclassified

Fire Barriers

(This Report)

Unclassified

15. NUMBER OF PAGES

16. PRICE

NRC FORM 335 (2-89)


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NUCLEAR REGULATORY COMMISSION

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