Information Notice No. 84-09, Revision 1: Lessons Learned from NRC Inspections of Fire Protection Safe Shutdown Systems (10 CFR 50, Appendix R)
SSINS No.: 6835
IN 84-09, Rev. 1
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
WASHINGTON, D.C. 20555
March 7, 1984
Information Notice No. 84-09, REVISION 1: LESSONS LEARNED FROM NRC
INSPECTIONS OF FIRE PROTECTION
SAFE SHUTDOWN SYSTEMS (10 CFR
50, APPENDIX R)
All nuclear power reactor facilities holding an operating license (OL) or
construction permit (CP).
This Information Notice is a revision to Information Notice No. 84-09
issued on February 13, 1984. Attachment 1 to this revision is a replacement
page which will accomplish a needed correction to subparagraph 4 of Section
III of Information Notice No. 84-09. The revision on page 2 is indicated in
comparative text and in the margin to highlight the change. Licensees
should add the replacement page 2. No specific action or response is
required as a result of this replacement.
If you have any questions regarding this matter, please contact the Regional
Administrator of the appropriate NRC regional office or this office.
Edward L. Jordan, Director
Division of Emergency Preparedness and
Office of Inspection and Enforcement
Technical Contacts: L. E. Whitney, IE
T. Wambach, NRR
Attachments: 1. Supplemental Guidance on 10 CFR 50 Appendix R Fire
Protection Safe Shutdown Requirements, Replacement page 2
2. List of Recently Issued IE Information Notices
IN 84-09, Rev. 1
March , 1984
Page 2 of 9
III. Protection of Equipment Necessary To Achieve Hot Shutdown
At one facility, redundant pressurizer heater control and power cables were
separated by a partial horizontal pyrocrete barrier suspended from the
overhead. At the same facility, two auxiliary feedwater pumps were located
adjacent to each other and separated by a partial steel missile shield
coated on one side with fire-retardant material. The separation criteria of
Appendix R, Section III.G.2, were not met in that the coated shield did not
meet the definition of a fire barrier of BTP APCSB 9.5-1. No alternative
means of feedwater supply was designated.
At a second facility, redundant pressurizer heater load centers were located
within the same cabinet. At a third facility, redundant steamline isolation
valve control cables for HPCI and RCIC pumps were located in close proximity
without a fire rated barrier.
Appendix R, Section III.G.1, requires that fire protection features shall be
provided for structures, systems, and components important to safe shutdown.
These features shall be capable of limiting fire damage so that one train of
systems necessary to achieve and maintain a hot shutdown condition from
either the control room or emergency control station(s) is free of fire
Sections III.G.2 and III.G.3 specify four alternatives that may be
implemented outside of primary containment to assure that one redundant
train of equipment, cabling and associated circuits necessary to achieve and
maintain hot shutdown remains free of fire damage. The alternatives are:
1. Separation of redundant trains of equipment, cabling and associated
circuits by a three-hour fire barrier.
2. Enclosure of redundant trains of equipment, cabling, and associated
circuits by a one-hour fire barrier with fire detection and automatic
fire suppression systems installed in the area.
3. Separation of redundant trains of equipment, cabling, and associated
circuits by a horizontal distance of 20 feet with no intervening
combustibles and with fire detection and automatic fire suppression
systems in the area.
4. Installation of alternative or dedicated shutdown capability independent
of the equipment, cabling, and associated circuits under consideration,
and installation of fire detection and fixed fire suppression systems in
* the area under consideration.
It should be note that Sections III.G.2.d, e and f of Appendix R, provide
additional options for the separation of redundant trains of equipment and
cables within non-inerted containments.
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