ML19256G307
| ML19256G307 | |
| Person / Time | |
|---|---|
| Issue date: | 11/27/1979 |
| From: | Grimes B Office of Nuclear Reactor Regulation |
| To: | Morrison W NRC OFFICE OF STANDARDS DEVELOPMENT |
| References | |
| NUDOCS 7912310013 | |
| Download: ML19256G307 (2) | |
Text
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UNITED STr,TEs j 'g.,- f ^;
NUCLEAR REGULATORY COMMISSION C
WASHINGTON. O. C. 20555 Mi,*,'.://,
~-+.q; j MEMORANDUM FOR:
W. M. Morrison, Assistant Director for General Engineering Standards, DES FROM:
Brian K. Grimes, Acting Assistant Director for Systems Engineering, 00R
SUBJECT:
STANDARDS REVIEW - ANS 59.2, "HVAC SYSTEMS, IMPORTANT TO SAFETY, LOCATED OUTSIDE PRIMARY CONTAINMENT" In response to your request, dated September 25, 1979, the Plant Systems Branch has performed a brief review of the above subject ANS Standard, concerning the design of the HVAC systems which are important to safety and located outside the primary containment.
Based on our review, we find that the draft standard should be modified to resolve the following cormients:
1.
Section 5.1.3 - Main Control Room HVAC Systems - The HVAC systems for the main control room should be specified to maintain a constant condition (constant relative humidity, constant temperature, etc.) required for the control instrumentation as well as required for the operators' comfort during all modes of plant operation and accident conditions.
2.
Section 5.1.8 - Chilled Water Systems - Any chilled water system which is designed to provice a heat sink for safety related HVAC cooling coils or heat exchangers must be redun-dant and be physically separated or ;rotected so that damage to one system does not preverit the associated HVAC system; from performing their safety function.
3.
Section 6.4 - Ducts - Ducts for all safety related HVAC systems and air cleaning systems shall confom to ANSI N-509.
4 Appendix A Section 1.0 - Safety Class Systems - Should add Section 1.10 to classify tne components of the Essential Chilled Water Systems (if any).
1660 226 791231 o o ]
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5.
Section 5.1.3 - Add to this section:
" Verification is 5:Lired to determine that the design of the HVAC system for :ne ain Control Room is consistent with LEEE Standard 567."
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/ Brian K. Grimes, Ac' ting Assistant Director for Systers Engineering Division of Operatinc Rea: ors
Contact:
D. Shum X-27058 cc:
D. Eisenhut R. Tedesco D
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D. Tondi R. Ferguson E. Adensam D. Shum G. Knighton T. Scarborough 1660 227