United States Nuclear Regulatory Commission - Protecting People and the Environment

Bulletin 79-01: Environmental Qualification of Class IE Equipment

                               UNITED STATES 
                           WASHINGTON, D.C. 20555
                              February 8, 1979

                                                  IE Bulletin No. 79-01 


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 

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. 

                                Page 1 of 3 

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 

                                Page 2 of 3 

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 

                                Page 3 of 3 

                                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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