1、IEEE Std 833-2005(Revision of IEEE Std 833-1988)IEEE Recommended Practice for theProtection of Electric Equipment inNuclear Power GeneratingStations from Water HazardsI E E E3 Park Avenue New York, NY10016-5997, USA19 May 2006IEEE Power Engineering SocietySponsored by theNuclear Power Engineering Co
2、mmitteeRecognized as anAmerican National Standard (ANSI)IEEE Std 833-2005(R2011)(Revision ofIEEE Std 833-1988)IEEE Recommended Practice for the Protection of Electric Equipment in Nuclear Power Generating Stations from Water HazardsSponsorNuclear Power Engineering Committee of the IEEE Power Enginee
3、ring Society Approved 21 April 2006American National Standards InstituteApproved 7 December 2005 Reaffirmed 7 December 2011 IEEE-SA Standards BoardThe Institute of Electrical and Electronics Engineers, Inc.3 Park Avenue, New York, NY 10016-5997, USACopyright 2006 by the Institute of Electrical and E
4、lectronics Engineers, Inc.All rights reserved. Published 19 May 2006. Printed in the United States of America.IEEE is a registered trademark in the U.S. Patent +1 978 750 8400. Permission to photocopy portions of any individual standard for educational classroom use can also be obtained through the
5、Copyright Clearance Center. ivCopyright 2006 IEEE. All rights reserved.IntroductionThis introduction is not part of IEEE Std 833-2005, IEEE Recommended Practice for the Protection of ElectricEquipment in Nuclear Power Generating Stations from Water Hazards. This recommended practice was originally d
6、eveloped in 1988 in response to concerns expressed relative tofailures of electric equipment in operating nuclear power plants resulting from water or moisture intrusion.The purpose of this document is to recommend practices that address these concerns and that are in additionto those that may alrea
7、dy be required or in place to protect the electric equipment or systems from waterhazards. This recommended practice describes design, installation, and maintenance considerations to protect electricequipment against potential water intrusion hazards. This recommended practice is intended to define
8、whena water hazard exists and provide useful practices as to how to deal with water hazards for operating plants,new plants, or during plant modifications. However, the individuality of each nuclear power plant structuremakes it difficult to provide specific directions. This document does not addres
9、s the ability of the electric equipment to withstand a “loss-of-coolant”accident, high energy line break, or the physical forces resulting from jet impingement, or other line breaksthat are covered by other analyses, standards, or requirements. Further, it may not be reasonable to provideprotection
10、for all possible flooding scenarios. Examples for such scenarios are multiple or simultaneous pipebreaks, valves leaks, or deliberate operations of fire hoses to extinguish fires in equipment. Areas that may be reviewed for possible inclusion in future revisions of this document are as follows: Race
11、way design issues Use of environmentally sealed splices and connectionsThis revision updates the document with current industry practice and operating experience. The principalchanges are the explanation of weep and drain holes application, and design considerations for potentialwater submergence in
12、 duct banks. Notice to usersErrataErrata, if any, for this and all other standards can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL forerrata periodically.InterpretationsCurrent interpretations can be access
13、ed at the following URL: http:/standards.ieee.org/reading/ieee/interp/index.html.PatentsAttention is called to the possibility that implementation of this standard may require use of subject mattercovered by patent rights. By publication of this standard, no position is taken with respect to the exi
14、stence orvalidity of any patent rights in connection therewith. The IEEE shall not be responsible for identifyingvCopyright 2006 IEEE. All rights reserved.patents or patent applications for which a license may be required to implement an IEEE standard or forconducting inquiries into the legal validi
15、ty or scope of those patents that are brought to its attention.ParticipantsAt the time this recommended practice was completed, the Working Group on Protection of Safety Systemsfrom Hazards of Water (SC 4.8) had the following membership:Robert J. Fletcher, ChairThe Working Group would like to acknow
16、ledge the contributions of Barry J. Skoras, who served as Chairmanfor much of the development of the recommended practice and to Pranab K. Guha, who contributed to thedevelopment of the document.The following members of the individual balloting committee voted on this standard. Balloters may havevot
17、ed for approval, disapproval, or abstention. Dale T. GoodneyKenneth GreeneS. K. MitraRoger D. ParkerSatish AggarwalStan J. ArnotVincent BacanskasFarouk BaxterWesley BowersRobert CarruthJohn CarterSurin DurejaRobert J. FletcherRonald FlueggeJulian Forster Wilmer GangloffDale T. GoodneyBritton GrimRan
18、dall GrovesKuljit HaraDavid A. HorvathPaul JohnsonTanuj KhandelwalJohn KueckHenry LeungJohn MacDonaldThomas McCaffreyJohn MerandoGary MichelGerald NicelyRoger D. ParkerJames RuggieriJordan ShikoskiJames StonerJames ThomasT. J. VossviCopyright 2006 IEEE. All rights reserved.When the IEEE-SA Standards
19、 Board approved this standard on 7 December 2005, it had the followingmembership:Steve M. Mills, ChairRichard H. Hulett, Vice ChairDon Wright, Past ChairJudith Gorman, Secretary*Member EmeritusAlso included are the following nonvoting IEEE-SA Standards Board liaisons:Satish K. Aggarwal, NRC Represen
20、tativeRichard DeBlasio, DOE RepresentativeAlan H. Cookson, NIST RepresentativeMichael D. FisherIEEE Standards Project EditorMark D. BowmanDennis B. BrophyJoseph BruderRichard CoxBob DavisJulian Forster*Joanna N. GueninMark S. HalpinRaymond HapemanWilliam B. HopfLowell G. JohnsonHerman KochJoseph L.
21、Koepfinger*David J. LawDaleep C. MohlaPaul NikolichT. W. OlsenGlenn ParsonsRonald C. PetersenGary S. RobinsonFrank StoneMalcolm V. ThadenRichard L. TownsendJoe D. WatsonHoward L. WolfmanCopyright 2006 IEEE. All rights reserved.viiContents1. Overview 11.1 Scope 11.2 Purpose. 12. Normative references.
22、 13. Definitions 24. Electric equipment protection 24.1 Location . 24.2 Equipment design. 24.3 Sealing and shielding . 25. Design and construction features for electric equipment rooms 35.1 General. 35.2 Room construction. 36. Electric equipment located in open areas subject to water hazards. 47. El
23、ectric equipment enclosures . 47.1 Application. 47.2 Enclosure designations. 47.3 Special conditions 48. Electric equipment installation practices . 58.1 General. 58.2 Electric equipment installed in locations that have no direct source of water hazard . 58.3 Electric equipment installed in location
24、s where water-hazard sources are present. 59. Electric equipment protection 69.1 Methods 69.2 Materials 69.3 Procedures 710. Maintenance, surveillance, and testing activities. 7Annex A (informative) Bibliography. 81 Copyright 2006 IEEE. All rights reserved. IEEE Recommended Practice for the Protecti
25、on of Electric Equipment in Nuclear Power Generating Stations from Water Hazards 1. Overview This recommended practice is divided into ten clauses. Clause 1 provides the scope and purpose of this recommended practice. Clause 2 lists references to other standards that are useful in applying this reco
26、mmended practice. Clause 3 provides a definition that is either not found in other standards, or has been modified for use with this recommended practice. Clause 4 through Clause 10 provide recommended methods and design features for water-hazard protection to the electric systems and equipment. Thi
27、s recommended practice also contains one annex. Annex A provides bibliographical references. 1.1 Scope This document presents recommended practices for providing the electric systems and equipment in nuclear power plants with protection from water hazards. 1.2 Purpose This document recommends method
28、s and design features that, if implemented, would provide water-hazard protection to Class 1E and non-Class 1E systems and equipment from direct sources of water (for example, water spray from decontamination activities) and indirect sources of water (for example, water running along cables and race
29、ways). It is not the purpose of this recommended practice to classify water-hazard protection features as nuclear safety related or non-nuclear safety related. This determination is application specific and is made by the user utilizing the specific nuclear generating station design basis and guidan
30、ce from other standards. 2. Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments or corrige
31、nda) applies. IEEE Std 833-2006 IEEE RECOMMENDED PRACTICE FOR THE PROTECTION OF ELECTRIC 2 Copyright 2006 IEEE. All rights reserved. IEEE Std C57.12.01, IEEE Standard General Requirements for Dry-Type Distribution and Power Transformers Including Those With Solid Cast and/or Resin-Encapsulated Windi
32、ngs.1,2IEEE Std 323, IEEE Standard for Qualifying Class IE Equipment for Nuclear Power Generating Stations. IEEE Std 634, IEEE Standard for Cable-Penetration Fire Stop Qualification Test. NEMA ICS 6, Industrial Control and Systems: Enclosures.33. Definitions For the purposes of this recommended prac
33、tice, the following terms and definitions apply. The Authoritative Dictionary of IEEE Standards, Seventh Edition B94, should be referenced for terms not defined in this clause. 3.1 water hazard: The abnormal presence of a quantity of water, either in the form of condensation, accumulation, flow, or
34、spray; not postulated to be associated with any design basis event; and considered likely to cause the loss of desired function of electric equipment in nuclear power plants if it enters such equipment. 4. Electric equipment protection 4.1 Location It is recommended that first consideration be given
35、 to locating electric equipment such that direct or indirect sources of water hazard will not be present. Next, locations should be considered that can be enclosed to restrict the entry of a water hazard or where design features can direct water hazards away from the equipment. 4.2 Equipment design
36、Where the foregoing preferred locations are not practical or desirable to implement, equipment design, selection, or modifications should be considered to make the equipment resistant to water hazards. 4.3 Sealing and shielding Additional protection from sources of water hazards are best accomplishe
37、d by proper sealing measures or physical shielding. This treatment should not interfere with ventilation or other design considerations (for example, seismic, thermal), or unduly restrict maintenance activities. It should be further understood that when water is to be applied directly to a specific
38、item of electric equipment as a means of extinguishing a fire in or on that equipment, sealing or shielding should not prevent this; however, any other electric equipment in the vicinity should not be adversely affected by this action. 1IEEE publications are available from the Institute of Electrica
39、l and Electronics Engineers, Inc., 445 Hoes Lane, Piscataway, NJ 08854, USA (http:/standards.ieee.org/). 2The IEEE standards or products referred to in this clause are trademarks of the Institute of Electrical and Electronics Engineers, Inc. 3NEMA publications are available from Global Engineering D
40、ocuments, 15 Inverness Way East, Englewood, CO 80112, USA (http:/ 4The numbers in brackets refer to the bibliography in Annex A. EQUIPMENT IN NUCLEAR POWER GENERATING STATIONS FROM WATER HAZARDS IEEE Std 833-2005 3 Copyright 2006 IEEE. All rights reserved. 5. Design and construction features for ele
41、ctric equipment rooms 5.1 General Electric equipment rooms located adjacent to areas where potential water hazards exist that could reasonably be postulated to enter the rooms should be designed and constructed to be resistant to the entry of water. Penetrations through walls, floors, and ceilings (
42、roofs) are high-risk areas and should be properly sealed to the extent necessary to preclude water-hazard intrusion. Water-filled piping located within, or penetrating electric equipment rooms should be avoided or assessed as to its potential to become a water hazard. If a source of water, which can
43、 be reasonably postulated to be a water hazard, exists in or is added to an equipment room area, electric equipment should be protected in accordance with the recommendations in Clause 6. 5.2 Room construction 5.2.1 Floor construction The preferred method of room entry by raceways and pipe is throug
44、h floor penetrations. These penetrations should be properly sealed to be resistant to water infiltration from beneath the floor if that potential for water hazard exists. Equipment room floors at the same level or lower than surrounding areas that contain water sources may become a water hazard area
45、. Electric equipment in such locations should be mounted on raised bases, or curbs should be provided, to direct water away from the electric equipment to floor drains. Floor drains, where provided, should be sized by plant analysis to remove all simultaneous flows of water into the equipment room.
46、Floor drains should be equipped with check valves or other suitable means if back flow can be realistically postulated and an unacceptable level of water would result and constitute a water hazard. Interconnection of drain lines between divisions should be avoided. 5.2.2 Wall construction Wall penet
47、rations are the second choice for entering electric equipment areas. Where this presents a potential for a water hazard, they should be properly sealed. 5.2.3 Ceiling (roof) construction The ceiling construction should be of a suitable design to be resistant to water due to rain, flooding from above
48、, or piping system leaks. Where the ceiling structure design loads are heavy, vibratory, or abrasive, these conditions should be considered in the design of the waterproofing system. Where a drop ceiling is utilized, an analysis should be performed to determine whether it is concealing a potential w
49、ater-hazard condition. Penetrations through the ceiling by raceways, piping, or ductwork are the least desirable. Where ceiling penetrations exist or are unavoidable, they should be sealed to be resistant to water seepage or leakage and should not be located directly above the equipment. IEEE Std 833-2006 IEEE RECOMMENDED PRACTICE FOR THE PROTECTION OF ELECTRIC 4 Copyright 2006 IEEE. All rights reserved. 5.2.4 Doors or other openings Doors or other openings in electric equipment rooms should be designed to be resistant to entry of water w
