1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12173:2012Chemicals used for treatmentof water intended for humanconsumption SodiumfluorideBS EN 12173:2012 BRITISH STANDARDNational forewordThis British Standard is the UK
2、 implementation of EN 12173:2012. Itsupersedes BS EN 12173:2005 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CII/59, Chemicals for drinking water treatment.A list of organizations represented on this committee can beobtained on request to its secreta
3、ry.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 77784 4ICS 13.060.20; 71.100.80Compliance with a British Standard
4、cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 November 2012.Amendments issued since publicationDate Text affectedBS EN 12173:2012EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12173 Octob
5、er 2012 ICS 71.100.80 Supersedes EN 12173:2005English Version Chemicals used for treatment of water intended for human consumption - Sodium fluoride Produits chimiques utiliss pour le traitement de leau destine la consommation humaine - Fluorure de sodiumProdukte zur Aufbereitung von Wasser fr den m
6、enschlichen Gebrauch - Natriumfluorid This European Standard was approved by CEN on 23 September 2012. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
7、Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management 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 tra
8、nslation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finl
9、and, 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, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATI
10、ON COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12173:2012: EBS EN 12173:2012EN 12173:2012 (E) 2 Contents Pa
11、ge Foreword 3Introduction . 41 Scope 52 Normative references 53 Description . 54 Purity criteria 75 Test methods 86 Labelling - Transportation - Storage 13Annex A (informative) General information on sodium fluoride 16Annex B (normative) General rules relating to safety . 17Bibliography 18BS EN 1217
12、3:2012EN 12173:2012 (E) 3 Foreword This document (EN 12173:2012) has been prepared by Technical Committee CEN/TC 164 “Water supply”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by en
13、dorsement, at the latest by April 2013, and conflicting national standards shall be withdrawn at the latest by April 2013. Attention 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 identi
14、fying any or all such patent rights. This document supersedes EN 12173:2005. The significant technical differences between this edition and EN 12173:2005 are as follows: Modification of 6.2 on labelling, deletion of the reference to EU Directive 80/778/EEC of 15 July 1980 in order to take account of
15、 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, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Re
16、public of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 12173:2012EN 12173:2012 (E) 4 Introduction In res
17、pect 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 whether the product may be used without restriction in any of the Member States of the EU or EFTA;
18、 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 Conformity with this European Standard does not confer or imply acceptance or approval of the pr
19、oduct 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. BS EN 12173:2012EN 12173:2012 (E) 5 1 Scope This European Standard is applicable to sodium fluoride used for treatment of water i
20、ntended for human consumption. It describes the characteristics of sodium fluoride and specifies the requirements and the corresponding test methods for sodium fluoride. It gives information on its use in water treatment. It also determines the rules relating to safe handling and use (see Annex B).
21、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 document (including any amend
22、ments) applies. EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696) ISO 2831, Sodium fluoride for industrial use Determination of water-insoluble matter ISO 2832, Sodium fluoride for industrial use Determination of moisture content ISO 2833, Sodium fluoride for
23、 industrial use Determination of fluorine content Modified Willard-Winter-method ISO 3165, Sampling of chemical products for industrial use Safety in sampling ISO 5993, Sodium hydroxide for industrial use Determination of mercury content Flameless atomic absorption spectrometric method ISO 6206, Che
24、mical 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 from powders to coarse lumps 3 Description 3.1 Ide
25、ntification 3.1.1 Chemical name Sodium fluoride. 3.1.2 Synonym or commons name Sodium fluoride. 3.1.3 Relative molecular mass 42. 3.1.4 Empirical formula NaF. BS EN 12173:2012EN 12173:2012 (E) 6 3.1.5 Chemical formula NaF.3.1.6 CAS-Registry Number 1)7681-49-4. 3.1.7 EINECS reference 2)231-667-8. 3.2
26、 Commercial form The product is a solid (crystals or powder). 3.3 Physical properties 3.3.1 Appearance and odour The product is a colourless fine crystalline odourless powder or crystals. 3.3.2 Density The density of the crystals is 2,8 g/cm3at 20 C. The bulk density of the product is 0,6 g/cm3to 1,
27、4 g/cm3at 20 C. 3.3.3 Solubility (in water) The solubility of the product in water is 40 g/l at 20C. 3.3.4 Vapour pressure Not applicable. 3.3.5 Boiling point at 100 kPa 3)The product boils at approximately 1 700 C. 3.3.6 Crystallisation point The product melts at approximately 988 C. 3.3.7 Specific
28、 heat Not known. 1) Chemical Abstracts Service Registry Number. 2)European Inventory of Existing Commercial Chemical Substances. 3)100 kPa = 1 bar. BS EN 12173:2012EN 12173:2012 (E) 7 3.3.8 Viscosity dynamic Not applicable. 3.3.9 Critical temperature Not applicable. 3.3.10 Critical pressure Not appl
29、icable. 3.3.11 Physical hardness Not applicable. 3.4 Chemical properties Sodium fluoride releases hydrogen fluoride when in contact with acids. 4 Purity criteria 4.1 General This European Standard specifies the minimum purity requirements for sodium fluoride used for the treatment of water intended
30、for human consumption. Limits are given for impurities commonly present in the product. Depending on the raw material and the 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
31、check the national regulations in order to clarify whether it is of appropriate purity for treatment of water intended for human consumption, taking into account raw water quality, required dosage, contents of other impurities and additives used in the products not stated in this product standard. L
32、imits have been given for impurities and chemical parameters where these are likely to be present in significant quantities from 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
33、present, this shall be notified to the user. 4.2 Composition of commercial product The content of sodium fluoride shall not be less than a mass fraction of 98 % (NaF). The concentration of sodium fluoride shall be within 5 % of the manufacturers declared value. 4.3 Impurities and main by-products Th
34、e product shall conform to the requirements specified in Table 1. Table 1 Impurities Impurity Limit in mass fraction in % of commercial product Water-insoluble matter max 0,5 Moisture max 0,5 BS EN 12173:2012EN 12173:2012 (E) 8 4.4 Chemical parameters The product shall conform to the requirements sp
35、ecified in Table 2. Table 2 Chemical parameters Parameter Limit mg/kg of commercial product Antimony (Sb) max 1 Arsenic (As) max 5 Cadmium (Cd) max 0,1 Chromium (Cr) max 4 Lead (Pb) max 4 Mercury (Hg) max 0,1 Nickel (Ni) max 4 Selenium (Se) max 1 NOTE Other chemical parameters and indicator paramete
36、rs are not relevant in sodium fluoride because the raw materials used in the manufacturing process are free of them. For parametric values of sodium fluoride on trace metal content in drinking water, see 1. 5 Test methods 5.1 Sampling Observe the general recommendations of ISO 3165 and take account
37、of ISO 6206. Prepare the laboratory sample(s) required by the relevant procedure described in ISO 8213. 5.2 Analyses 5.2.1 General All reagents shall be of a recognised analytical grade and the water used shall conform to the grade 3 specified in EN ISO 3696. 5.2.2 Main product The mass fraction of
38、fluorine (C1) in % shall be determined in accordance with ISO 2833. The sodium fluoride content, C2, expressed as mass fraction in % is given by the following formula: C2= C1x 2,2101 (1) BS EN 12173:2012EN 12173:2012 (E) 9 5.2.3 Impurities 5.2.3.1 Water-insoluble matter The content of insoluble matt
39、er shall be determined in accordance with ISO 2831. 5.2.3.2 Moisture The content of moisture shall be determined in accordance with ISO 2832. 5.2.4 Chemical parameters 5.2.4.1 General The content of chemical parameters shall be determined using the procedures specified in Table 3. Table 3 Procedures
40、 for the determination of chemical parameters Element Reference Method Wavelength nm Flame As see 5.2.4.3 Hydride AAS 193,7 n.a. Sb see 5.2.4.3 Hydride AAS 217,6 n.a. Cd ISO 6353-1 GM 29 See 5.2.4.2 AAS 228,8 air-acetylene Cr ISO 6353-1 GM 29 See 5.2.4.2 AAS 357,8 air-acetylene Pb ISO 6353-1 GM 29 S
41、ee 5.2.4.2 AAS 217,0 or 283,3 air-acetylene Ni ISO 6353-1 GM 29 See 5.2.4.2 AAS 232,0 oxidising air-acetylene Se see 5.2.4.3 Hydride AAS 196,0 n.a. Hg in accordance with ISO 5993 flameless AAS 253,6 n.a. AAS = Atomic absorption spectrometry n.a. = not applicable. 5.2.4.2 Determination of cadmium (Cd
42、), chromium (Cr), lead (Pb) and nickel (Ni) 5.2.4.2.1 General The content of Cd, Cr, Pb and Ni shall be determined taking into account ISO 6353-1, modified as described in 5.2.4.2.2. 5.2.4.2.2 Procedure The elements Cd, Cr, Pb and Ni shall be determined using the standard addition method. The refere
43、nce solutions shall be made by spiking the sample with standard solutions, which contain stepwise increasing contents of the elements to be determined. The amount of internal standard to be added can be estimated from a preliminary investigation, determining roughly the element content of the test s
44、ample from simple calibration. The steps in which internal standards are added shall be at least as high as the estimated content of the test sample. Carry out a blank determination by repeating the procedure using the same quantities of all reagents but omitting the test sample. BS EN 12173:2012EN
45、12173:2012 (E) 10 5.2.4.2.3 Expression of results Determine the correlation line by plotting the measured absorbencies of the spiked measurement solutions in relation to the element content. The spiked measurement solutions are produced by adding defined quantities of element to the measurement solu
46、tion. They contain stepwise increasing contents of the elements to be determined. Read the concentration of each element in the test solution by extrapolation of the correlation line to absorbance A = 0 (see Figure 1). Similarly determine the element concentration of the blank solution (see Figure 2
47、) and subtract from the result obtained for the test solution. Alternatively, the evaluation can be carried out by linear regression. Additional dilution steps shall be compensated in the calculation. This interim result (y) expressed in micrograms per litre needs to be converted to give the final c
48、oncentration according to the formula in 5.2.4.2.4. 5.2.4.2.4 Calculation From the interim result (y) determined (see 5.2.4.2.3) the content, C3, of each element in the laboratory sample, expressed in milligrams per kilogram of sodium fluoride, is given by the following formula: 22330001100CmVyC= (2
49、)where y is the interim result (5.2.4.2.3); V3 is the volume, expressed in millilitres, of the test solution; m2is the mass ,expressed in grams ,of the test portion; C2is the content, expressed in mass fraction in % of sodium fluoride (see 5.2.2). BS EN 12173:2012EN 12173:2012 (E) 11 Key 1 concentration of added standard in micrograms per litre 2 absorbance A 3 concentration in the test solution in micrograms per litre A1; A2;A3 spiking Figure 1 Calculation of the element concentrati
