Bulletin 79-01B: Environmental Qualification of Class IE Equipment
SSINS No.: 6820
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
WASHINGTON, D.C. 20555
January 14, 1980
IE Bulletin No. 79-01B
ENVIRONMENTAL QUALIFICATION OF CLASS IE EQUIPMENT
Description of Circumstances:
IE Bulletin No. 79-01 required the licensee to perform a detailed review of
the environmental qualification of Class IE electrical equipment to ensure
that the equipment will function under (i.e. during and following)
postulated accident conditions.
The NRC staff has completed the initial review of licensees' responses to
Bulletin No. 79-01. Based on this review, additional information is needed
to facilitate completion of the NRC evaluation of the adequacy of
environmental qualification of Class IE electrical equipment in the
operating facilities. In addition to requesting more detailed information,
the scope of this Bulletin is expanded to resolve safety concerns relating
to design basis environments and current qualification criteria not
addressed in the facilities' FSARS. These include high energy line breaks
(HELB) inside and outside primary containment, aging, and submergence.
Enclosure 4, "GUIDELINES FOR EVALUATING ENVIRONMENTAL QUALIFICATION OF GLASS
IE ELECTRICAL EQUIPMENT IN OPERATING REACTORS", provides the guidelines and
criteria the staff will use in evaluating the adequacy of the licensee's
Class, IE equipment evaluation in response to this Bulletin.
In general, the reporting problems encountered in the original responses and
the additional information needed can be grouped into the following areas:
1. All Class IE electrical equipment required to function under the
postulated accident conditions, both inside and outside primary
containment, was not included in the responses.
2. In many cases, the specific information requested by the Bulletin for
each component of Class IE equipment was not reported.
3. Different methods and/or formats were used in providing the written
evidence of Class IE electrical equipment qualifications. Some
licensees used the System Analysis Method which proved to be the most
effective approach. This method includes the following information:
a. Identification of the protective plant systems required to
function under postulated accident conditions. The postulated
accident conditions are defined as those environmental conditions
resulting from both LOCA and/or HELB inside primary containment
and HELB outside the primary containment.
IE Bulletin No. 79-01B January 14, 1980
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b. Identification of the Class IE electrical equipment items within
each of the systems identified in Item a, that are required to
function under the postulated accident conditions.
c. The correlation between the environmental data requirements
specified in the FSAR and the environmental qualification test
data for each Class IE electrical equipment item identified in
Item b above.
4. Additional data not previously addressed in IE Bulletin No. 79-01 are
needed to determine the adequacy of the environmental qualification of
Class IE electrical equipment. These data address component aging and
operability in a submerged condition.
Action To Be Taken By Licensees Of All Power Reactor Facilities With An
Operating License (Except those 11 SEP Plants Listed on Enclosure 1)
1. Provide a "master list" of all Engineered Safety Feature Systems (Plant
Protection Systems) required to function under postulated accident
conditions.Accident conditions are defined as the LOCA/HELB inside
containment, and HELB outside containment. For each system within
(including cables, EPA's terminal blocks, etc.) the master list
identify each Class IE electrical equipment item that is required to
function under accident conditions. Pages 1 and 2 of Enclosure 2 are
standard formats to be used for the "master list" with typical
Electrical equipment items, which are components of systems listed in
Appendix A of Enclosure 4, which are assumed to operate in the FSAR
safety analysis and are relied on to mitigate design basis events are
considered within the scope of this Bulletin, regardless whether or not
they were classified as part of the engineered safety features when the
plant was originally licensed to operate. The necessity for further up
grading of nonsafety-related plant systems will be dependent on the
outcome of the licensees and the NRC reviews subsequent to TMI/2.
2. For each class IE electrical equipment item identified in Item I,
provide written evidence of its environmental qualification to support
the capability of the item to function under postulated accident
conditions. For those class IE electrical equipment items not having
adequate qualification data available, identify your plans for
determining qualifications of these items and your schedule for
completing this action. Provide this in the format of Enclosure 3.
3. For equipment identified in Items 1 and 2 provide service condition
profiles (i.e., temperature, pressure, etc., as a function of time).
These data should be provided for design basis accident conditions and
qualification tests performed. This data may be provided in profile or
IE Bulletin No. 79-01B January 14, 1980
Page 3 of 3
4. Evaluate the qualification of your Class IE electrical equipment
against the guidelines provided in Enclosure 4. Enclosure 5, "Interim
Staff Position on Environmental Qualification of Safety-Related
Electrical Equipment," provides supplemental information to be used
with these guidelines. For the equipment identified as having
"Outstanding Items" by Enclosure 3, provide a detailed "Equipment
Qualification Plan." Include in this plan specific actions which will
be taken to determine equipment qualification and the schedule for
completing the actions.
5. Identify the maximum expected flood level inside the primary
containment resulting from postulated accidents. Specify this flood
level by elevation such as the 620 foot elevation. Provide this
information in the format of Enclosure 3.
6. Submit a "Licensee Event Report" (LER) for any Class IE electrical
equipment item which has been determined as not being capable of
meeting environmental qualification requirements for service intended.
Send the LER to the appropriate NRC Regional Office within 24 hours of
identification. If plant operation is to continue following
identification, provide justification for such operation in the LER.
Provide a detailed written report within 14 days of identification to
the appropriate NRC Regional Office. Those items which were previously
reported to the NRC as not being qualified per IEB-79-01 do not require
7. Complete the actions specified by this bulletin in accordance with the
(a) Submit a written report required by Items 1, 2, and 3 within 45
days from receipt of this Bulletin.
(b) Submit a written report required by Items 4 and 5 within 90 days
from receipt of this Bulletin.
This information is requested under the provisions of 10 CFR 50.54(f).
Accordingly, you are requested to provide within the time periods specified
in Items 7.a and 7.b above, written statements of the above information,
signed under oath or affirmation.
Submit the reports to the Director of the appropriate NRC Regional Office.
Send a copy of your report to the U.S. Nuclear Regulatory Commission, Office
of Inspection and Enforcement, Division of Reactor Operations Inspection,
Washington, D.C. 20555.
Approved by GAO, B180225 (ROO72); clearance expires 7/31/80. Approval was
given under a blanket clearance specifically for identified generic
Dresden 1 III
Yankee Rowe I
Big Rock Point III
San Onofre 1 V
Haddam Neck I
Oyster Creek I
R. E. Ginna I
Dresden 2 III
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