Bulletin 79-01: Environmental Qualification of Class IE Equipment
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
WASHINGTON, D.C. 20555
February 8, 1979
IE Bulletin No. 79-01
ENVIRONMENTAL QUALIFICATION OF CLASS IE EQUIPMENT
Description of Circumstances:
The intent of IE Circular 78-08 was to highlight to all licensees important
lessons learned from environmental qualification deficiencies reported by
individual licensees. In this regard, licensees were requested to examine
installed safety-related electrical equipment and determine that proper
documentation existed which provided assurance that this equipment would
function under postulated accident conditions. The scope of IE Circular
78-08 was much broader than other previously issued Bulletins and Circulars
(such as IEB 78-04 and IEB 78-02) which addressed specific component
failures. The intent of this Bulletin is to raise the threshold of IE
Circular 78-08 to the level of a Bulletin; action requiring a licensee
response.
Inspections conducted to date by the NRC of licensees' activities in
response to IE Circular 78-08 have identified one component which licensees
have found to be unqualified for service within the LOCA environment.
Specifically, unqualified stem mounted limit switches (SMLS), other than
those identified in previously issued IE Bulletin 78-04, were found to be
installed on safety-related valves inside containment at both Duane Arnold
and Quad Cities 1 and 2 Nuclear Generating Stations. The unqualified
switches are identified as NAMCO Models SL2-C-11, S3CML, SA1-31, SA1-32,
D1200j, EA-700 and EA-770 switches. According to the manufacturer, these
switches are designed only for general purpose applications and are not
considered suitable devices for service in the LOCA environment.
Consequently, switches are being replaced at the above power plants with
qualified components.
Also, NRC inspection of component qualification has identified equipment
which does not have documentation indicating it is qualified for the LOCA
environment. The inspections have also identified that the licensee'
re-review and resolution of problem areas are not receiving the level of
attention from all licensees which the NRC believes is warranted. Because of
the protracted schedule for completion of the re-review, we are now
requesting the power reactor facilities with operating licenses to expedite
completion of their re-review program originally requested by IE Circular
78-08 dated May 31, 1978.
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IE Bulletin No. 79-01 February 8, 1979
Action to Be Taken By Licensees of All Power Reactor Facilities (Except
Those 11 SEP Plants Listed on Enclosure 3) With An Operating License:
1. Complete the re-review program described in IE Circular 78-08 within
120 days of receipt of this Bulletin.
2. Determine if the types of stem mounted limit switches described above
are being used or planned for use on safety-related valves which are
located inside containment at your facility. If so, provide a written
report to the NRC within the time frame specified and to the address
specified in Item 4 below.
3. Provide written evidence of the qualification of electrical equipment
required to function under accident conditions.* For those items not
having complete qualification data available for review, identify your
plans for determining qualification, either by testing or engineering
analysis, or combination of these, or by replacement with qualified
equipment. Include your schedule for completing these actions and your
justification for continued operation.
Submit this information to the Director, Division of Reactor Operations
Inspection, Office of Inspection and Enforcement, Nuclear Regulatory
Commission, Washington, D.C. 20555 with a copy to the appropriate NRC
Regional Office within 120 days of receipt of this.
4. Report any items which are identified as not meeting qualification
requirements for service intended to the Director, Division of
Operating Reactors, Office of Nuclear Reactor Regulation, Nuclear
Regulatory Commission, Washington, D.C. 20555 with a copy to the
appropriate NRC Regional Office within 24 hours of identification. If
plant operation is to continue following identification, provide
justification for such operation. Provide detailed written report
within 14 days of identification to NRR, with a copy to the appropriate
NRC Regional Office.
* This written evidence should include: 1) component description; 2)
description of the accident environment; 3) the environment to which
the component or equipment is qualified; 4) the manner of qualification
which should include test methods such as sequential, synergistic,
etc., and 5) identification of the specific supporting qualification
documentation.
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IE Bulletin No. 79-01 February 8, 1979
No additional written response to this IE Bulletin is required other than
those responses described above. NRC inspectors will continue to monitor the
licensees' progress in completing the requested action described above. If
additional information is required, contact the Director of the appropriate
NRC Regional Office.
Approved by GAO B180225 (R0072); clearance expires 7/31/80. Approval was
given under a blanket clearance specifically for identified generic
problems.
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SEP Plants
Plant Region
Dresden 1 III
Yankee Rowe I
Big Rock Point III
San Onofre 1 V
Haddam Neck I
LaCrosse III
Oyster Creek I
R. E. Ginna I
Dresden 2 III
Millstone I
Palisades III
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