1、BRITISH STANDARDBS EN ISO 11844-1:2008Corrosion of metals and alloys Classification of low corrosivity of indoor atmospheres Part 1: Determination and estimation of indoor corrosivity ICS 77.060g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38
2、g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 11844-1:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 April 2006 BSI 2008ISBN 978 0 580 60544 4National forewordThis British Stan
3、dard is the UK implementation of EN ISO 11844-1:2008. It is identical with ISO 11844-1:2006. It supersedes BS ISO 11844-1:2006 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee ISE/NFE/8, Corrosion of metals and alloys.A list of organizations represented
4、 on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corri
5、genda issued since publicationDate Comments29 August 2008 This corrigendum renumbers BS ISO 11844-1:2006 as BS EN ISO 11844-1:2008EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 11844-1April 2008ICS 77.060English VersionCorrosion of metals and alloys - Classification of low corrosivityof indoo
6、r atmospheres - Part 1: Determination and estimation ofindoor corrosivity (ISO 11844-1:2006)Corrosion des mtaux et alliages - Classification de lacorrosivit faible des atmosphres dintrieur - Partie 1:Dtermination et estimation de la corrosivit desatmosphres dintrieur (ISO 11844-1:2006)Korrosion von
7、Metallen und Legierungen - Einteilung derKorrosivitt in Rumen mit geringer Korrosivitt - Teil 1:Bestimmung und Abschtzung der Korrosivitt in Rumen(ISO 11844-1:2006)This European Standard was approved by CEN on 21 March 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations wh
8、ich stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Sta
9、ndard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national stan
10、dards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United King
11、dom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 11844-1:2008: Eii F
12、oreword The text of ISO 11844-1:2006 has been prepared by Technical Committee ISO/TC 156 “Corrosion of metals and alloys” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 11844-1:2008 by Technical Committee CEN/TC 262 “Metallic and other inorganic coating
13、s” the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2008, and conflicting national standards shall be withdrawn at the latest by October 2008. Atten
14、tion is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of
15、the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slova
16、kia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 11844-1:2006 has been approved by CEN as a EN ISO 11844-1:2008 without any modification. iiiContents Page Introduction v 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 2 4 Symbols an
17、d abbreviations . 2 5 Classification of corrosivity. 3 5.1 General. 3 5.2 Categories of indoor corrosivity . 3 6 Determination of indoor atmospheric corrosivity . 3 7 Characterization of indoor atmospheres with respect to indoor corrosivity . 3 7.1 General. 3 7.2 Estimation of indoor corrosivity . 4
18、 Annex A (informative) Relation between ISO, IEC and ISA classification systems 6 Annex B (informative) Outdoor and indoor concentrations of some of the most important pollutants in different types of environments .9 Annex C (informative) General characterisation of metal corrosion in indoor atmosph
19、eres 10 Annex D (informative) Guideline for estimation of indoor corrosivity 13 Bibliography . 16 BS EN ISO 11844-1:2008blankvIntroduction Metals, alloys and metallic coatings are subject to atmospheric corrosion under the impact of air humidity, especially when gaseous and solid substances of atmos
20、pheric pollution co-impact. Corrosivity data are of fundamental importance for derivation of suitable corrosion protection, or for evaluation of serviceability of metal elements of a product. ISO 9223 classifies the atmospheric environment into 5 corrosivity categories. Low-corrosivity indoor atmosp
21、heres are indoor atmospheres with C 1 (very low) or C 2 (low) corrosivity categories according to ISO 9223. The classification in ISO 9223 is too broad for some purposes in low-corrosivity indoor atmospheres, e.g. places where electronic devices, sophisticated technical products, or works of art and
22、 historical objects are stored. For such purposes, it is necessary to subdivide the corrosivity categories C 1 (very low) and C 2 (low) into indoor corrosivity categories in this part of ISO 11844. The evaluation of low-corrosivity indoor atmospheres can be accomplished by direct determination of co
23、rrosion attack of selected metals (see ISO 11844-2) or by measurement of environmental parameters (see ISO 11844-3) which may cause corrosion on metals and alloys. This part of ISO 11844 describes general procedures for derivation and estimation of indoor corrosivity categories. A general approach t
24、o classification of corrosivity in indoor atmospheres is given in the scheme shown in Figure 1. BS EN ISO 11844-1:2008vi Figure 1 Scheme for classification of low corrosivity in indoor atmospheres BS EN ISO 11844-1:20081Corrosion of metals and alloys Classification of low corrosivity of indoor atmos
25、pheres Part 1: Determination and estimation of indoor corrosivity 1 Scope This part of ISO 11844 deals with the classification of low corrosivity of indoor atmospheres. The aim of this part of ISO 11844 is to characterise indoor atmospheric environments of low corrosivity that can affect metals and
26、metallic coatings during storage, transport, installation or operational use, to set a consistent way of indoor corrosivity classification, and to prescribe procedures for derivation and estimation of indoor corrosivity categories. This part of ISO 11844 specifies technical metals, whose corrosion a
27、ttack after a defined exposure period is used for determination of corrosivity categories of indoor atmospheres of low corrosivity. This part of ISO 11844 defines corrosivity categories of indoor atmospheres according to corrosion attack on standard specimens. This part of ISO 11844 indicates import
28、ant parameters of indoor atmospheres that can serve as a basis for an estimation of indoor corrosivity. Selection of a method for determination of corrosion attack, description of standard specimens, its exposure conditions and evaluation are the subject of ISO 11844-2. Measurement of environmental
29、parameters affecting indoor corrosivity is the subject of ISO 11844-3. 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
30、document (including any amendments) applies. ISO 9223:1992, Corrosion of metals and alloys Corrosivity of atmosphere Classification ISO 11844-2:2005, Corrosion of metals and alloys Classification of low corrosivity of indoor atmospheres Part 2: Determination of corrosion attack in indoor atmospheres
31、 BS EN ISO 11844-1:20082 ISO 11844-3:1), Corrosion of metals and alloys Classification of low corrosivity of indoor atmospheres Part 3: Measurement of environmental parameters affecting indoor corrosivity IEC 60654-4:1987, Operating conditions for industrial-process measurement and control equipment
32、. Part 4: Corrosive and erosive influences 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 corrosivity of atmospheres ability of the atmosphere to cause corrosion in a given corrosion system (e.g. atmospheric corrosion of a given metal or all
33、oy) ISO 9223:1992, definition 3.1 3.2 temperature-humidity complex combined effect of temperature and relative humidity on the corrosivity of the atmosphere ISO 9223:1992, definition 3.5 3.3 time of wetness period during which a metallic surface is covered by adsorptive and/or liquid films of electr
34、olyte that are capable of causing atmospheric corrosion ISO 9223:1992, definition 3.2 3.3.1 calculated time of wetness time of wetness estimated from the temperature-humidity complex ISO 9223:1992, definition 3.2.1 3.3.2 experimental time of wetness time of wetness indicated directly by various meas
35、uring systems ISO 9223:1992, definition 3.2.2 3.4 atmospheric pollution specific corrosion-active substances, gases or suspended particles in the air (both natural and the result of human activity) 4 Symbols and abbreviations IC corrosivity categories of indoor atmospheres. rcorrcorrosion rate deriv
36、ed from mass-loss measurement after an exposure of one year. rmirate of mass increase after an exposure of one year. 1) To be published. BS EN ISO 11844-1:200835 Classification of corrosivity 5.1 General The corrosivity of indoor atmospheres can be classified either by determination of the corrosion
37、 attack on standard specimens of selected standard metals as given in Clause 6 or, where this is not possible, by estimation of corrosivity based on the knowledge of humidity, temperature and pollution conditions as described in Clause 7 and informative Annexes B, C and D. Estimation of corrosivity
38、as described in 7.2. and Annexes C and D may lead to wrong conclusions. Therefore, the determination of corrosivity by measurement of the corrosion attack on standard specimens is strongly recommended. 5.2 Categories of indoor corrosivity For the purpose of this part of ISO 11844, indoor atmospheres
39、 are classified into 5 corrosivity categories denoted IC 1 to IC 5. The classification is given in Table 1. Table 1 Corrosivity categories of indoor atmospheres Indoor corrosivity category IC 1 Very low indoor corrosivity IC 2 Low indoor corrosivity IC 3 Medium indoor corrosivity IC 4 High indoor co
40、rrosivity IC 5 Very high indoor corrosivity 6 Determination of indoor atmospheric corrosivity The determination of corrosivity of indoor atmospheres is based on measurements of corrosion attack on standard specimens of four reference metals after an exposure for one year in accordance with ISO 11844
41、-2. From the mass loss or mass increase, the indoor corrosivity category for each metal is determined from Table 2. Metals complement each other in the classification of indoor corrosivity for a given environment. 7 Characterization of indoor atmospheres with respect to indoor corrosivity 7.1 Genera
42、l Environmental characteristics are informative and allow assessment of specific corrosion effects with regard to individual metals and metallic coatings. Methods for characterization and measurement of environmental parameters in indoor atmospheres are given in ISO 11844-3. This method of corrosivi
43、ty estimation is, in many cases, oversimplified and may give misleading results. An estimation of corrosivity is based on climatic influences (outdoor situation including pollution), indoor microclimate influences, and indoor gaseous and particle pollution. BS EN ISO 11844-1:20084 The corrosivity of
44、 an indoor atmosphere increases with higher humidity and depends on the type and level of pollution. Frequency of variation of relative humidity (RH) and temperature (T) in intervals, and frequency and time of condensation, are important characteristics. Indoor atmospheres are polluted by the compon
45、ents from external and internal sources. Typical pollutants are SO2, NO2, O3, H2S, Cl2, NH3,HCl, HNO3,Cl, NH4+, organic acids, aldehydes and particles (see informative Annex B). Corrosion for many of the metals is significantly influenced by the synergistic effects of different pollutants. Metals an
46、d metallic coatings have their own specific corrosion behaviour in indoor atmospheres (see informative Annex C). 7.2 Estimation of indoor corrosivity 7.2.1 Characterization of the environment summarised in a guideline (Annex D), forms a basis for indoor corrosivity estimation. Description of typical
47、 environments related to the estimation of indoor corrosivity categories is presented in Table D.3. 7.2.2 Important factors of indoor corrosion are defined as the highest levels of measured environmental parameters and as a description of other and specific environmental influences affecting indoor
48、corrosion of metals. 7.2.3 The determination of indoor corrosivity categories is illustrated in Tables 2 and 3. Table 2 Classification of corrosivity of indoor atmospheres based on corrosion rate measurements by mass loss determination of standard specimens Corrosion rate (rcorr) mg/(m2a) Corrosivit
49、y category Carbon steel Zinc Copper Silver IC 1 Very low indoor rcorru 70 rcorru 50 rcorru 50 rcorru 170 IC 2 Low indoor 70 50 % 70 %) with periodic fluctuation of relative humidity, without risk of condensation, elevated levels of pollution, low risk of specific pollutants, e.g. churches in non-polluted areas, outdoor telecommunication boxes in rural areas IC 4 high indoor Heated spaces with fluctuation of humidity and temperature, elevated levels of pollution including specific pollutants, e.g. electrical service
