1、February 2013 Translation by DIN-Sprachendienst.English price group 11No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).I
2、CS 71.100.80!$R=“1944726www.din.deDDIN EN 12125Chemicals used for treatment of water intended for humanconsumption Sodium thiosulfate;English version EN 12125:2012,English translation of DIN EN 12125:2013-02Produkte zur Aufbereitung von Wasser fr den menschlichen Gebrauch Natriumthiosulfat;Englische
3、 Fassung EN 12125:2012,Englische bersetzung von DIN EN 12125:2013-02Produits chimiques utiliss pour le traitement de leau destine la consommationhumaine Thiosulfate de sodium;Version anglaise EN 12125:2012,Traduction anglaise de DIN EN 12125:2013-02SupersedesDIN EN 12125:2005-09www.beuth.deIn case o
4、f doubt, the German-language original shall be considered authoritative.Document comprises 19 pages 02.13 DIN EN 12125:2013-02 2 A comma is used as the decimal marker. National foreword This document (EN 12125:2012) has been prepared by Technical Committee CEN/TC 164 “Water supply” (Secretariat: AFN
5、OR, France). The responsible German body involved in its preparation was the Normen-ausschuss Wasserwesen (Water Practice Standards Committee), Working Committee NA 119-04-02 AA Wasseraufbereitung. Users of this standard are advised of the reservations stated in the Introduction of the European Stan
6、dard and should note that national regulations exist in Germany dealing with water for human consumption, in particular the Trinkwasserverordnung (TrinkwV2001) (German Drinking Water Ordinance). The DIN Standards corresponding to the International Standards referred to in this document are as follow
7、s, whereby EN ISO Standards are only listed below if these have not been published as DIN EN ISO Standards with the same number: EN ISO 3696 DIN ISO 3696 Amendments This standard differs from DIN EN 12125:2005-09 as follows: a) the reference to Directive 67/548/EEC relating to the classification, pa
8、cking and labelling of dangerous substances has been replaced by the reference to Regulation EC No 1272/2008. Previous editions DIN EN 12125: 1998-12, 2005-09 National Annex NA (informative) Bibliography DIN ISO 3696, Water for analytical laboratory use Specification and test methods Verordnung ber
9、die Qualitt von Wasser fr den menschlichen Gebrauch (Trinkwasserverordnung TrinkwV 2001) (German Drinking Water Ordinance), as of 28 November 2011 (BGBI. I p. 2370), as amended by Article 2, Paragraph 19 of the Act of 22 December 2011 (BGBI. I p. 3044)*)*)Obtainable from: Bundesministerium der Justi
10、z (German Federal Ministry of Justice) (Internet: http:/www.gesetze-im-internet.de). EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12125 November 2012 ICS 71.100.80 Supersedes EN 12125:2005English Version Chemicals used for treatment of water intended for human consumption - Sodium thiosulfat
11、e Produits chimiques utiliss pour le traitement de leau destine la consommation humaine - Thiosulfate de sodium Produkte zur Aufbereitung von Wasser fr den menschlichen Gebrauch - Natriumthiosulfat This European Standard was approved by CEN on 23 September 2012. CEN members are bound to comply with
12、the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Managem
13、ent Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same statu
14、s as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
15、 Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of
16、 exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12125:2012: EEN 12125:2012 (E) 2 Contents Page Foreword 3Introduction .41 Scope 52 Normative references 53 Description .54 Purity criteria 75 Test methods 86 Labelling Transportation Storage . 14Annex
17、 A (informative) General information on sodium thiosulfate . 15Bibliography . 17DIN EN 12125:2013-02EN 12125:2012 (E) 3 Foreword This document (EN 12125:2012) has been prepared by Technical Committee CEN/TC 164 “Water supply”, the secretariat of which is held by AFNOR. This European Standard shall b
18、e given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2013, and conflicting national standards shall be withdrawn at the latest by May 2013. Attention is drawn to the possibility that some of the elements of this document may be
19、 the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 12125:2005. The significant technical differences between this edition and EN 12125:2005 are as follows: Modification of 6.2 on labelling, deleti
20、on of the reference to EU Directive 80/778/EEC of 15 July 1980 in order to take account of the latest Directive in force. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium
21、, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerla
22、nd, Turkey and the United Kingdom. DIN EN 12125:2013-02EN 12125:2012 (E) 4 Introduction In respect of potential adverse effects on the quality of water intended for human consumption caused by the product covered by this European Standard: a) this European Standard provides no information as to whet
23、her the product may be used without restriction in any of the Member States of the EU or EFTA; b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations concerning the use and/or the characteristics of this product remain in force. NOTE Co
24、nformity with this European Standard does not confer or imply acceptance or approval of the product in any of the Member States of the EU or EFTA. The use of the product covered by this European Standard is subject to regulation or control by National Authorities. DIN EN 12125:2013-02EN 12125:2012 (
25、E) 5 1 Scope This European Standard is applicable to sodium thiosulfate used for treatment of water intended for human consumption. It describes the characteristics and specifies the requirements of sodium thiosulfate and refers to the corresponding analytical methods. It gives information for its u
26、se in water treatment. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced docume
27、nt (including any amendments) applies. EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696) ISO 3165, Sampling of chemical products for industrial use Safety in sampling ISO 5993, Sodium hydroxide for industrial use Determination of mercury content Flameless ato
28、mic absorption spectrometric method ISO 6206, Chemical products for industrial use Sampling Vocabulary ISO 6353-1, Reagents for chemical analysis Part 1: General test methods ISO 8213, Chemical products for industrial use Sampling techniques Solid chemical products in the form of particles varying f
29、rom powders to coarse lumps ISO 10636, Photography Processing chemicals Specifications for anhydrous sodium thiosulfate and sodium thiosulfate pentahydrate ISO 22743, Water quality Determination of sulfates Method by continuous flow analysis (CFA) 3 Description 3.1 Identification 3.1.1 Chemical name
30、 Sodium thiosulfate. 3.1.2 Synonym or commons names Sodium thiosulfate, sodium hyposulfite. 3.1.3 Relative molecular mass 158,11 (anhydrous). 3.1.4 Empirical formula Na2S2O3. DIN EN 12125:2013-02EN 12125:2012 (E) 6 3.1.5 Chemical formula Na2S2O3. 3.1.6 CAS-Registry Number 1)7772-98-7 (anhydrous); 10
31、102-17-7 (pentahydrate). 3.1.7 EINECS reference 2)231-867-5. 3.2 Commercial form The product is a crystalline powder. 3.3 Physical properties 3.3.1 Appearance The hydrated product is colourless crystal. The anhydrous product is a white powder. 3.3.2 Density The particle density of the hydrated produ
32、ct is 1,69 g/cm3to 1,73 g/cm3at 20 C. 3.3.3 Solubility in water The solubility of the product in water is 700 g/l at 20 C (anhydrous); for pentahydrate : 2910 g/l at 45 C. 3.3.4 Vapour pressure Not applicable. 3.3.5 Boiling point at 100 kPa 3)Not applicable. 3.3.6 Crystallisation point The product s
33、tarts to decompose at 45 C to 50 C. 3.3.7 Specific heat Not known. 1) Chemical Abstracts Service Registry Number. 2) European Inventory of Existing Commercial Chemical Substances. 3) 100 kPa = 1 bar. DIN EN 12125:2013-02EN 12125:2012 (E) 7 3.3.8 Viscosity, dynamic Not applicable. 3.3.9 Critical temp
34、erature Not applicable. 3.3.10 Critical pressure Not applicable. 3.3.11 Physical hardness Not applicable. 3.4 Chemical properties The pH value of a diluted aqueous solution of sodium thiosulfate is approximately neutral (6,5 to 8). Sodium thiosulfate dissolves silver halogenids and other silver salt
35、s. At elevated temperatures ( 50 C), sulfur dioxide is generated. Sodium thiosulfate releases sulfur dioxide when mixed with acids. Sodium thiosulfate reacts violently with oxidising agents; e.g. with sodium hypochlorite or hydrogen peroxide. It shall not come into contact with acids, iodine, lead a
36、nd silver salts. 4 Purity criteria 4.1 General This European Standard specifies the minimum purity requirements for sodium thiosulfate used for the treatment of water intended for human consumption. Limits are given for impurities commonly present in the product. Depending on the raw material and th
37、e manufacturing process other impurities may be present and, if so, this shall be notified to the user and when necessary to relevant authorities. Users of this product should check the national regulations in order to clarify whether it is of appropriate purity for treatment of water intended for h
38、uman consumption, taking into account raw water quality, required dosage, contents of other impurities and additives used in the product not stated in this product standard. Limits have been given for impurities and chemical parameters where these are likely to be present in significant quantities f
39、rom the current production process and raw materials. If the production process or raw materials leads to significant quantities of impurities, by-products or additives being present, this shall be notified to the user. 4.2 Composition of commercial product The concentration of sodium thiosulfate an
40、hydrous shall not be less than a mass fraction of 95 % of Na2S2O3. The concentration of sodium thiosulfate pentahydrate shall not be less than a mass fraction of 95% of Na2S2O3.5 H2O. DIN EN 12125:2013-02EN 12125:2012 (E) 8 4.3 Impurities and main by-products The content of sodium sulfate shall not
41、exceed a mass fraction of 5 % . 4.4 Chemical parameters The product shall conform to the requirements specified in Table 1. Table 1 Chemical parameters Parameter Limitmg/kg of commercial product Antimony (Sb) max 2 Arsenic (As) max 0,5 Cadmium (Cd) max 0,1 Chromium (Cr) max 5 Lead (Pb) max 5 Mercury
42、 (Hg) max 0,1 Nickel (Ni) max 5 Selenium (Se) max 2 NOTE Pesticides and polycyclic aromatic hydrocarbons and cyanides (CN ) are not relevant in sodium thiosulfate because the raw materials used in the manufacturing are free of them. For parametric values of sodium thiosulfate on trace metal content
43、in drinking water, see 1. 5 Test methods 5.1 Sampling Observe the general recommendations of ISO 3165 and take account of ISO 6206. Prepare the laboratory sample(s) required by the relevant procedure described in ISO 8213. 5.2 Analyses 5.2.1 Main product The sodium thiosulfate content shall be deter
44、mined in accordance with ISO 10636. 5.2.2 Impurities 5.2.2.1 Sulfate The content of sodium sulfate (Na2SO4) shall be determined in accordance with ISO 22743. DIN EN 12125:2013-02EN 12125:2012 (E) 9 5.2.3 Chemical parameters 5.2.3.1 General The content of chemical parameters shall be determined using
45、 the procedures specified in Table 2: Table 2 Procedures for the determination of chemical parameters Element Reference Method Wavelength (nm) Flame As see 5.2.3.3 Hydride AAS 193,7 n.a.Sb see 5.2.3.3 Hydride AAS 217,6 n.a. Cd ISO 6353-1 GM 29see 5.2.3.2 AAS 228,8 air-acetylene Cr ISO 6353-1 GM 29se
46、e 5.2.3.2 AAS 357,8 air-acetylene Pb ISO 6353-1 GM 29see 5.2.3.2 AAS 217,0 or 283,3 air-acetylene Ni ISO 6353-1 GM 29see 5.2.3.2 AAS 232,0 oxidising acetylene-air Se see 5.2.3.3 Hydride AAS 196,0 n.a.Hg in accordance withISO 5993 flameless AAS 253,6 n.a. AAS = Atomic Absorption Spectroscopy. n.a. =
47、not applicable. 5.2.3.2 Determination of cadmium (Cd), chromium (Cr), lead (Pb) and nickel (Ni) 5.2.3.2.1 Principle The elements cadmium (Cd), chromium (Cr), lead (Pb) and nickel (Ni) are determined using atomic absorption spectrometry with the standard additions technique. 5.2.3.2.2 Reagents All re
48、agents shall be of a recognised analytical grade and the water used shall conform to the grade 3 specified in EN ISO 3696. 5.2.3.2.2.1 Standard solution (100 g/l Cd, Cr ,Pb or Ni) The standard solution shall be freshly prepared on the day of use by individual dilution of a stock solution. This stock solution with a Cd, Cr, Pb or Ni content of at least 1 mg/l shall be made by dilution of standard solutions of Cd, Cr, Pb and Ni which are available from all major s
