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Bulletin 79-01B: Supplement Information, Environmental Qualification of Class IE Equipment

                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
                    OFFICE OF INSPECTION AND ENFORCEMENT
                           WASHINGTON, D.C. 20555
                                     
                              February 29, 1980

                                                    IE Bulletin No. 79-01B 
                                                    Supplement  Information 

ENVIRONMENTAL QUALIFICATION OF CLASS IE EQUIPMENT 

Enclosed are the generic questions and answers which resulted from NRC Task 
Group/Licensee "workshop" meetings held recently in NRC Regional Offices 
regarding IE Bulletin No. 79-01B. This information is intended to further 
the understanding of the qualification review process and reporting 
requirements of the Bulletin. 

The further intent of this information is to assist the licensees in 
providing a method of approach acceptable to the assigned NRC Task Review 
Group in determining adequacy of the environmental qualification of Class IE
Electrical Equipment installed at their respective facilities. 

It should be recognized that the review of the licensee's responses may 
generate additional need for guidance of finalized resolution of the 
environmental qualification issue. 

Enclosure:
Generic Questions and Answers
  to IE Bulletin No. 79-01B
.

          GENERIC QUESTIONS AND ANSWERS TO IE BULLETIN No. 79-01B 


Question 1     IEB 79-01B indicates the scope of the task is only that 
               equipment exposed to a harsh environment. Enclosure 4, 
               Section 4.3.3 identified areas outside of containment not 
               exposed to harsh environmental conditions as the results of 
               an accident. Should these areas be included in our 
               evaluations? 

Answer 1       No. Although the guidelines encompass all safety-related 
               electrical equipment and components, the scope of IEB 79-01B 
               is limited to only that electrical equipment which is exposed
               to the harsh environments identified in action item 1, 
               including where fluids are recirculated from inside 
               containment to accomplish long-term cooling following a LOCA.
               All equipment and components identified in action item shall 
               be included in the subsequent actions required by IEB 79-01B.

Question 2     IEB 79-01B action item 1 and Enclosure 4 indicate that 
               emergency procedures be used to identify equipment to be 
               included in the master list. Should all the equipment 
               identified in the emergency procedures be included in the 
               master list? 

Answer 2       All the equipment the licensee relies upon in the emergency 
               procedures to mitigate design basis events that may be 
               exposed to a harsh environment must be identified in response 
               to Question 1. It is not the intent of this task to change 
               the existing procedures by removing references to equipment 
               or comments that are considered nonessential and not 
               environmental qualified. This master list identifies all 
               equipment and components that must be evaluated in response 
               to action item 4. A determination should be made that 
               sufficient equipment is environmentally qualified to permit 
               accident mitigation. A tabulation of other equipment or 
               components which are referenced in the Emergency Procedures 
               but are not relied upon should be available for NRC review. 
               Justification should also be available so that non-qualified 
               equipment will not be misleading to the operator. 

Question 3     Is not 2 of Appendix A to Enclose 4 within the scope of this 
               task. 

Answer 3       Only those emergency shutdown systems that could be used for 
               mitigation of a LOCA or HELB and are exposed to a harsh 
               environment identified in response to Question 1. Licensee 
               review should: (1) identify equipment that could be used to 
               achieve cold shutdown following LOCA or HELB; and (2) 
               determine if environmental qualification exists. For 
               equipment that is not environmentally qualified the licensee 
               should either provide plans to qualify this equipment or 
               provide justification that qualification is not needed to 
               achieve safe shutdown to meet licensing requirements 
               applicable to your facility. 
.

                                    - 2 -

Question 4     What is the basis for the 340 Degrees F for 6 hours 
               requirement identified in Enclosure 4 and NUREG 0588, Figure 
               C 1? 

Answer 4       For minimum high temperature conditions in pressure 
               suppression type containments, we do not require that 340 
               Degrees F for 6 hours be used for BWR drywells or that 340 
               Degrees F for 3 hours be used for PWR ice condenser lower 
               compartments. These values are from a bounding high 
               temperature profile (see section 1.1 and 1.2 of NUREG 0588) 
               that can be used in lieu of a plant specific profile, 
               provided that expected pressure and humidity conditions as a 
               function of time are accounted for. 

               In general, the containment temperature and pressure 
               conditions as a function of time should be based on analyses 
               in the FSAR. However, these conditions should bound that 
               expected for coolant and steam line breaks inside the 
               containment. The steam line break conditions should include 
               superheated conditions: the peak temperature, and subsequent 
               temperature/pressure profile as a function of time. If 
               containment spray is to be used, the impact of the spray on 
               required equipment should be accounted for. 

Question 5     Should equipment or systems which are presently planned to be
               modified as a result of actions, such as lessons learned, to 
               be included in the response to IEB 79-01B? 

Answer 5       No. 

Question 6     Will there be any other actions required when the NRC 
               completes its evaluation of the responses to IEB 79-01B and 
               any related corrective actions deemed necessary are complete?

Answer 6       The NRC staff does not foresee any additional actions for the
               electrical equipment and components which are included in the
               scope of IEB 79-01B; however, if new problems or concerns are
               identified, appropriate action will be taken. 

Question 7     Are Spare Parts required to meet 79-01B? 

Answer 7       Yes. The Spare Parts are required to meet the same criteria 
               as the installed electrical equipment or component resulting 
               from the evaluation of IEB 79-01B. 

Question 8     The instruction sheet for Enclosure 3 "System Component 
               Evaluation" indicates that outstanding items be identified. 
               What is the definition of outstanding items? 
.

                                    - 3 -

Answer 8       An outstanding item is defined as that item that does not 
               meet the environmental qualification guidelines and 
               requirements of IEB 79-01. 

Question 9     Are the requirements and positions in NUREG 0588 the same as 
               those in NUREG 0578 in relation to environmental 
               qualification of electrical equipment and components? 

Answer 9       Yes. 

Question 10    NUREG 0588 is out for comment. Does the staff expect any 
               significant changes which may impact this effort? 

Answer 10      No. 

Question 11    When it is determined, as a result of the efforts required by
               IEB 79-01B, that specific equipment be upgraded, are the 
               guidelines in Enclosure 4 to be used? 

Answer 11      As a minimum the same requirements that were used to 
               determine the acceptability of the electrical equipment and 
               components within the scope of IEB 79-013 may be used; 
               however, if equipment is available which meets the 
               requirements of IEEE 323-1974 it should be used. 

Question 12    Does the Licensee Event Report (LER) requirements of IEB 
               79-01B supercede or chance the reporting requirements already
               defined? 

Answer 12      No. The requirement for reporting in IEB 70-01B does not 
               change the reporting requirements defined in the license 
               conditions. 

Question 13    Are only those items known to be unqualified immediately 
               reportable whereas items for which there is no data or 
               insufficient data are open items to be resolved, but are not 
               immediately reportable? 

Answer 13      When a determination has been made that the existing data is 
               inadequate or no data exists to have reasonable assurance 
               that the Class IE electrical equipment components can perform 
               their safety-related function required in the specified FSAR 
               environments, that is reportable per IEB 79-01B. The time and 
               technical judgments required to make the determination should 
               be based on the significance of the specific equipment, 
               components and the discrepancies. 
.

                                    - 4 -

Question 14    Are the results of an evaluation using the materials 
               identified in Enclosure 4, Appendix C, ,of an acceptable 
               method of addressing the effects of aging within the scope of
               Bulletin 79-01B? 

Answer 14      Yes, for those materials on the list, however, Appendix C  
               indicates this is a partial list. Your evaluation in response
               to IEB 79-018 may identify other materials that are 
               susceptible to significant degradation. 

Question 15    What are the sources Appendix C-1 used to identify the 
               material's in Table C-1 and establish the failure levels? 

Answer 15      Typical sources for the information are given in Appendix C. 
               Your information of materials not on this table should 
               identify the source for your evaluation. 

Question 16    Is additional effort or calculations required for radiation 
               service conditions if previous efforts did not utilize the 
               methodology or assumptions identified in NUREG 0588? 

Answer 16      Yes, the extent of the effort required will be dependent on 
               the significance of the difference in methodology and 
               assumptions. 

Question 17    Will extension of time be granted for schedules if identified
               in IEB 79-01B action item 7. 

Answer 17      The schedule was based on the significance of the safety 
               concerns relating to the adequacy of environmental 
               qualification of electrical equipment or components. Any 
               projected deviations from these schedules should be 
               identified to the Regional Office by a written request. The 
               NRC staff will make a determination on a case-by-case basis. 
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