Information Notice No. 79- 14, NRC Position of Electrical Cable Support Systems
June 4, 1979
MEMORANDUM FOR: B. H. Grier, Director, Region I
J. P. O'Reilly, Director, Region II
J. G. Keppler, Director, Region III
K. V. Seyfrit, Director, Region IV
R. H. Engelken, Director, Region V
FROM: Harold D. Thornburg, Director, RCI:IE
SUBJECT: Information Notice No. 79- 14, NRC POSITION OF
ELECTRICAL CABLE SUPPORT SYSTEMS
The subject Information Notice is transmitted for issuance on June 11, 1979.
The Information Notice should be issued to all power reactor facilities with
a construction permit. Also enclosed is a draft copy of the transmittal
letter for this purpose.
A copy of the memorandum R. J. Mattson to H. D. Thornburg and R. S. Boyd,
dated February 21, 1979, is forwarded for your information. This letter
provided the basis for this Information Notice but should not be distributed
with the Notice.
Harold D. Thornburg, Director
Division of Reactor Construction
Office of Inspection and Enforcement
1. IE Information Notice
2. Draft Transmittal Letter
3. Memorandum dated 2/21/79
CONTACT: W. Laudan, IE
(Draft letter to all applicants for, and holders of construction permits.)
Information Notice No. 79- 14
This Information Notice is being issued to call to your attention an aspect
of the Commission's regulations which IE inspectors have found is not always
being fully implemented. No written response is required. If you have
questions regarding this matter, please contact me.
IE Information Notice
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
WASHINGTON, D.C. 20555
June 11, 1979
Information Notice No. 79-14
SAFETY CLASSIFICATION OF ELECTRICAL CABLE SUPPORT SYSTEMS
The NRC inspection staff has found that in several cases, facilities under
construction have not applied the pertinent quality assurance requirements
of 10 CFR 50, Appendix B to the design, procurement, and installation of
cable trays and their support systems for Class IE electrical cables. This
notice is being issued to all applicants for, and holders of construction
permits, to remind them of the Commission's regulations on this subject.
Description of Circumstances:
1. In the Commission's Regulations for Licensing of Production and
Utilization Facilities - 10 CFR Part 50, Criterion 2 of Appendix A,
states in part that "Structures, systems and components important to
safety shall be designed to withstand the effects of....earthquakes
....without loss of capability to perform their safety functions...."
2. The Commission's Regulations on Reactor Site Criteria, Part 100,
Appendix A, define a "safe shutdown earthquake," (SSE) and generally
identify the structures, systems and components which are required to
remain functional during such an earthquake.
3. Regulatory Guide 1.29 "Seismic Design Classification" states in
"C.1. The following structures, systems and components of a nuclear
power plant, including their foundations and supports (emphasis added)
are designated as Seismic Category 1 and should be designed to
withstand the effects of the SSE and remain functional. The pertinent
quality assurance requirements of Appendix B to 10 CFR 50 should be
applied to all activities affecting the safety related functions of
these structures, systems and components."
"C1.q. The Class IE electric systems, including the auxiliary systems
for the on-site electric power supplies, that provide the emergency
No written response to this information notice is required. If you have
question's regarding the matter, please contact the Director of the
appropriate NRC Regional Office.
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