IEC_60079-9-1970_scan.pdf

一3一CONTENTSPageFOREWORDPREFACE,Clause1.Scope72.Object73.MarkingAPPENDIX-Symbols used by national or other appropriate authorities in certain countries toindicate that electrical apparatus meets their requirements for use in explosive gasatmospheres.80-5-INTERNATIONAL ELECTROTECHNICAL COMMISSIONELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERESPart 9:MarkingFOREWORD1)The formal decisions or agreements of the IEC on technical matters,prepared by Technical Committees on which all theNational Committees having a special interest thercin are represented,express,as nearly as possible,an internationalconsensus of opinion on the subjects dealt with.2)They have the form of recommendations for international use and they are accepted by the National Committees in thatsense.3)In order to promote this international unification,the IEC expresses the wish that all National Committees having asyet no national rules,when preparing such rules,should use the IEC recommendations as the fundamental basis for theserules in so far as national conditions will permit.4)The desirability is recognized of extending international agreement on these matters through an endeavour to harmonizenational standardization rules with these recommendations in so far as national conditions will permit.The NationalCommittees pledge their influence towards that end.The IEC has not laid down any procedure concerning marking as an indication of approval and has no responsibilitywhen an item of equipment is declared to comply with one of its recommendations.PREFACEThis Recommendation has been prepared by IEC Technical Committee No.31,Electrical Apparatus for Explosive Atmo-spheres.It forms one of a series of publications dealing with electrical apparatus for use in explosive gas atmospheres.Some ofthese publications are concerned with particular techniques.Others,of which this is one,are relevant to all techniques.The following parts of Publication 79 have already been published:Flameproof enclosures(see Publication 79*)Pressurized enclosures(see Publication 79-2)Testing of intrinsically safe apparatus(see Publication 79-3)Method of test for ignition temperature(see Publication 79-4)Sand-filled apparatus(see Publication 79-5)Oil-immersed apparatus(see Publication 79-6)Type e apparatus(see Publication 79-7)Classification of maximum surface temperatures(see Publication 79-8).A description of the techniques available for making electrical apparatus safe for use in gas atmospheres,with general _guidance on the subject,is in course of preparation.A draft dealing with the system of marking was discussed at the meeting held in Ottawa in 1966 and separate drafts of theecommendation and the Appendix were submitted to the National Committees for approval under the Six Months Rule inNovember 1967.The following countries voted explicitly in favour of publication of Part 9:AustraliaNetherlandsAustria*NorwayBelgiumPolandCanadaRomaniaCzechoslovakiaSouth AfricaDenmarkSwedenFinlandSwitzerlandFranceTurkeyGermanyUnion of Soviet Socialist RepublicsIranUnited KingdomIsraelUnited States of AmericaItalyYugoslaviaJapan*When the 1957 edition of Publication 79 is revised,the number will be changed to 79-1.*Did not vote explicitly in favour of publication of the Appendix.FOR REFERENCE ONLY7IANDARDS AND SAFETY SFCTIONV4THINA EERGY AUTHORITYELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERESPart 9:Marking1.ScopeThis Part of IEC Publication 79 describes the system of marking adopted by the IEC for identifyingelectrical apparatus intended for use in explosive gas atmospheres and constructed in accordance withother Parts of IEC Publication 79.Note.-It is important,in the interest of safety,that this system of marking should not be used for apparatus which is notcovered by IEC Publication 79 or which does not comply in all respects with the appropriate part of this Publication.2.ObjectThe object of this Recommendation is to enable electrical apparatus constructed in accordance withIEC Publication 79 to be readily identified,according to the method of protection adopted.3.MarkingThe recognized system of marking is as follows:a)The letters IEC.b)The number 79 followed by a hyphen and the number of the appropriate Part of IECPublication 79.c)The appropriate group symbol:I:for application in coal mining;II:for application in other industries.d)For certain methods of protection only,the appropriate sub-group symbol,e.g.“A,B,C.e)Marking in accordance with IEC Publication 79-8 to indicate the maximum surface temperature.f)The name or symbol of the national or other appropriate authority and the number of the cer-tificate or the approval number.Notes 1.-The full requirements for marking a given enclosure or piece of apparatus are given in the appropriatepart of IEC Publication 79.They include marking additional to that given above.2.-The following is an example of marking in accordance with a),b),c),d)and e)above:IEC79-1 IIAT33.-The symbols at present used by the various national and other appropriate authorities are given inthe Appendix.9SymboleSymbolPaysRemarquesCountryRemarksMinesAutres industriesOther industriesLe symbole CSA nindi-que la certification pourles atmospheres explo-sives que sil est accom-CanadaFPSEpagne de la designationappropriee de la zoneEM&Rdangereuse.The CSA symbol onlyindicates certification forexplosive atmospheres ifaccompanied by the ap-propriate hazardous lo-cation designation.La partie superieure dusymbole est completeepar linscription dunnumero qui indique lemode de protection.Lapartie inferieure est com-pletee par Iinscriptiondune ou deux lettres,dont la premiere ne sap-plique quaux enveloppesantideflagrantes et indi-que le groupe de gazTchecoslovaquiepour lequel le materielCzechoslovakiaest convenable.La lettre M indique le methaneExet ne sapplique quaumateriel pour les mines.La deuxieme lettre in-dique la classe de tempera-ture et ne figure pas surle materiel pour les mines.The upper part of thesymbol is completed byadding a number toindicate the method ofprotection.The lowerpart is completed byinserting one or twoletters,of which the firstis used for flameproofenclosures only and in-dicates the group ofgases for which the ap-paratus is suitable;Mindicates methane andapplies to mining equip-ment only.The secondletter indicates the tem-perature class and doesnot appear on miningequipment.