1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-21765-5 SANS 52931:2008Edition 1EN 12931:2000Edition 1SOUTH AFRICAN NATIONAL STANDARD Chemicals used for treatment of water intended for h
4、uman consumption Chemicals for emergency use Sodium dichloroisocyanurate, anhydrous This national standard is the identical implementation of EN 12931:2000 and is adopted with the permission of CEN, rue de Stassart 36, B-1050 Brussels. Published by Standards South Africa 1 dr lategan road groenkloof
5、 private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 52931:2008 Edition 1 EN 12931:2000 Edition 1 Table of changes Change No. Date Scope National foreword This South African standard was approved by National Commi
6、ttee StanSA TC 5140.19, Water, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This SANS document was published in July 2008. EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 12931April 2000ICS 71.100.80English versionChemicals used for
7、treatment of water intended for humanconsumption - Chemicals for emergency use - Sodiumdichloroisocyanurate, anhydrousProduits chimiques utiliss pour le traitement de leaudestine la consommation humaine - Produits chimiquesutiliss en cas durgence - Dichloroisocyanurate de sodium,anhydreProdukte zur
8、Aufbereitung von Wasser fr denmenschlichen Gebrauch - Produkte fr den Notfall -Natriumdichloroisocyanurat, wasserfreiThis European Standard was approved by CEN on 22 March 2000.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this Eu
9、ropeanStandard 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 Central Secretariat or to any CEN member.This European Standard exists in three official versions (English,
10、 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 Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Czech Republic, D
11、enmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCentral Secretariat: rue de Stassart, 36 B-1050
12、 Brussels 2000 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12931:2000 ESANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .Page 2EN 12931:2000ContentsPageForewo
13、rd3Introduction .41 Scope 52 Normative references 53 Description .53.1 Identification.53.2 Commercial form63.3 Physical properties63.4 Chemical properties 74 Purity criteria74.1 Composition of commercial product .74.2 Impurities and main by-products .74.3 Toxic substances.75 Test methods85.1 Samplin
14、g.85.2 Analysis 86 Labelling - Transportation - Storage146.1 Means of delivery.146.2 Risk and safety labelling according to the EU directives146.3 Transportation regulations and labelling 156.4 Marking .156.5 Storage16Annex A (informative) General information on sodium dichloroisocyanurate, anhydrou
15、s.17Annex B (normative) General rules relating to safety 19Annex C (normative) Determination of arsenic, antimony and selenium (atomic absorptionspectrometry hydride technique).21Bibliography 28SANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing client
16、s of the SABS .Page 3EN 12931:2000ForewordThis European Standard has been prepared by Technical Committee CEN/TC 164 “Water supply “, the secretariatof which is held by AFNOR.This European Standard shall be given the status of a national standard, either by publication of an identical text orby endo
17、rsement, at the latest by October 2000, and conflicting national standards shall be withdrawn at the latestby October 2000.According to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium
18、, Czech Republic, Denmark, Finland,France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden,Switzerland and the United Kingdom.Annex A is informative.The annexes B and C are normative.SANS 52931:2008This s tandard may only be used and printed by appr
19、oved subscription and freemailing clients of the SABS .Page 4EN 12931:2000IntroductionIn respect of potential adverse effects on the quality of water intended for human consumption, caused by theproduct covered by this Standard :a) this Standard provides no information as to whether the product may
20、be used without restriction in any of theMember States of the EU or EFTA ;b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulationsconcerning the use and/or the characteristics of this product remain in force.SANS 52931:2008This s tandard
21、may only be used and printed by approved subscription and freemailing clients of the SABS .Page 5EN 12931:20001 ScopeThis European Standard is applicable to sodium dichloroisocyanurate anhydrous used for emergency treatment ofwater intended for human consumption. It describes the characteristics of
22、anhydrous sodium dichloroisocyanurateanhydrous and specifies the requirements and the corresponding test methods for sodium dichloroisocyanurateanhydrous. It gives information on its use in water treatment.2 Normative referencesThis European Standard incorporates by dated or undated reference, provi
23、sions from other publications. Thesenormative references are cited at the appropriate places in the text and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions of any of these publications apply to this EuropeanStandard only when incorporated in it by a
24、mendment or revision. For undated references the latest edition of thepublication referred to applies.EN ISO 3696, Water for analytical laboratory use - Specification and test methods (ISO 3696:1987).ISO 3165, Sampling of chemical products for industrial use - Safety in sampling.EN 1483, Water quali
25、ty Determination of mercury.ISO 6206, Chemical products for industrial use - Sampling Vocabulary.ISO 8213, Chemical products for industrial use - Sampling techniques - Solid chemical products in the form ofparticles varying from powders to coarse lumps.ISO 8288, Water quality - Determination of coba
26、lt, nickel, copper, zinc, cadmium and lead - Flame atomicabsorption spectrometric methods.ISO 9174, Water quality - Determination of chromium - Atomic absorption spectrometric methods.3 Description3.1 Identification3.1.1 Chemical name1-sodium - 3,5-dichloro - 1,3,5-triazine - 2,4,6-trione.3.1.2 Syno
27、nym or common nameSodium dichloroisocyanurate.3.1.3 Relative molecular mass219,98.3.1.4 Empirical formulaC3N3O3Cl2Na.SANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .Page 6EN 12931:20003.1.5 Chemical formulaNaNC = ON - CICOO = C
28、CI - N3.1.6 CAS Registry Number1)2893-78-9.3.1.7 EINECS reference2)2-207-67-7.3.2 Commercial formThe product is available in various granular forms.3.3 Physical properties3.3.1 Appearance and odourThe product is a white granular solid with chlorinous odour.3.3.2 DensityThe bulk density is approximat
29、ely 0,9 g/cm3.3.3.3 Solubility in waterThe solubility in water is 250 g/l at 25 C.3.3.4 Vapour pressureNot applicable.3.3.5 Boiling point at 100 kPa3)Not applicable, the product decomposes before fusion.1) Chemical Abstracts Service Registry Number.2) European Inventory of Existing Commercial Chemic
30、al Substances.3) 100 kPa = 1 bar.SANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .Page 7EN 12931:20003.3.6 Melting pointNot applicable.3.3.7 Specific heat(1 090 40) J/kg K at 20 C.3.3.8 Viscosity, (dynamic)Not applicable.3.3.9 C
31、ritical temperatureNot applicable.3.3.10 Critical pressureNot applicable.3.3.11 Physical hardnessNot applicable.3.4 Chemical propertiesThe product is a strong oxidant, it is corrosive and hygroscopic ; sodium dichloroisocyanurate decomposes intohydrochloric acid and cyanuric acid. When dissolved in
32、a excess of water it liberates chlorine by hydrolysis.4 Purity criteriaLimits have been given for impurities and toxic substances where these are likely to be present in significantquantities from the current production process and raw materials. If a change in the production process or rawmaterials
33、 leads to significant quantities of other impurities or by-products being present, this shall be notified to theuser.4.1 Composition of commercial productThe product shall contain at least 62 percent by mass (% (m/m) of available chlorine.4.2 Impurities and main by-productsThe water content shall be
34、 less than 3 % (m/m) of the productThe sodium chloride content shall be less than 0,05 % (m/m) of the product.4.3 Toxic substancesNOTE For the purpose of this standard, “toxic substances“ are those defined in the EU Directive 80/778/EEC of 15 July,1980 (see 1).The content of toxic substances shall c
35、onform to the requirements specified in Table 1.SANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .Page 8EN 12931:2000Table 1 - Toxic substancesElementLimit mg/kgof productType 1 Type 2Arsenic (As) max. 10 10Cadmium (Cd) max. 1 1C
36、hromium (Cr) max. 6 10Mercury (Hg) max. 0,02 0,02Nickel (Ni) max. 3 5Lead (Pb) max. 4 15Antimony (Sb) max. 5 5Selenium (Se) max. 1 1NOTE Cyanide which does not exist in a strong oxidizing medium suchas sodium dichloroisocyanurate is not a relevant toxic substance.Pesticides and polycyclic aromatic h
37、ydrocarbons are not by-products ofthe manufacturing process.5 Test methods5.1 SamplingObserve the general recommendations of ISO 3165 and take account of ISO 6206. Prepare the laboratorysample(s) required by the relevant procedure described in ISO 8213.5.2 Analysis5.2.1 Determination of available ch
38、lorine (main product)5.2.1.1 PrincipleThe available chlorine is determinated by measuring active chlorine in the sample. The oxidizing chlorine reactswith potassium iodide releasing iodine which is then titrated with sodium thiosulfate standard volumetric solution inthe presence of starch indicator
39、solution.5.2.1.2 ReagentsAll reagents shall be of a recognized analytical grade and the water used shall conform to grade 3 in accordancewith EN ISO 3696.5.2.1.2.1 Potassium iodide crystals (KI).5.2.1.2.2 Glacial acetic acid.5.2.1.2.3 Sodium thiosulfate standard volumetric solution, c(Na2S2O3.5H2O)
40、= 0,1 mol/lDissolve 24,8 g of Na2S2O3.5H2O with water. Add 0,5 ml of chloroform as preservative, dilute to volume with waterin a 1000 ml one-mark volumetric flask and mix thoroughly.SANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing clients of the SAB
41、S .Page 9EN 12931:2000To standardize : weigh, to the nearest 0,1 mg, (160 10) mg (m)of primary standard potassium dichromate into atared glass beaker. Place the contents of the beaker in a 500 ml stoppered conical flask, add 100 ml of water and(2 0,5) g of potassium iodide and stir to dissolve. Add
42、(15 1) ml of hydrochloric acid solution (diluted 1+1 byvolume) swirl and allow to stand for 5 min. Titrate with the sodium thiosulfate solution until the solution is paleyellow. Add (5 1) ml of starch solution (5.2.1.2.4) and titrate to the end point, i.e. to the disappearance of the blue-black colo
43、ur. Record the volume (V) used.The concentration, c, of the sodium thiosulfate standard volumetric solution (Na2S2O35H2O), expressed in molesper litre is given by the following equation :031749, Vmcwherem is the mass, in milligrams, of potassium dichromate (K2Cr2O7) weighed ;V is the volume, in mill
44、ilitres, of the sodium thiosulfate standard volumetric solution used ;49,0317 is the molar mass, in grams per mole of potassium dichrormate (61K2Cr2O7).5.2.1.2.4 Starch solution, 1 % (m/m).Make a slurry with (1 0,1) g starch and (5 1) ml water. Add (90 5) ml boiling water to the slurry. Stir to diss
45、olveit and cool the solution. This solution needs refrigeration to avoid the decomposition of the starch which results in avague end point. Keep the solution cool and use it within one week.NOTE Commercial indicators for iodine titration exist and can be used in place of the specified starch solutio
46、n providedthat their efficiency has been previously tested.5.2.1.3 ApparatusOrdinary laboratory apparatus and glassware.5.2.1.4 Procedure5.2.1.4.1 Test portionWeigh, to the nearest 0,1 mg, 0,25 g of the laboratory sample (m0) into a tared stoppered weighing bottle.5.2.1.4.2 DeterminationTransfer the
47、 test portion to a 200 ml volumetric flask.Add 10 ml of water and 10 ml of glacial acetic acid (5.2.1.2.2), stir for 5 min and then add 100 ml of water and 2 gof potassium iodide (5.2.1.2.1), mix to dissolve and wait 10 min. Titrate with the sodium thiosulfate standardvolumetric solution (5.2.1.2.3)
48、 to a light yellow colour. Add 5 ml of the starch solution (5.2.1.2.4) and continuetitration to the disappearance of the blue black colour. Record the volume (V1) of the sodium thiosulfate standardvolumetric solution used.5.2.1.5 Expression of resultsThe chlorine (Cl2) content, C1, expressed as a pe
49、rcentage by mass (%) (m/m), is given by the following equation :1000035450011mcVC,SANS 52931:2008This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .Page 10EN 12931:2000whereV1is the volume, in millilitres, of the sodium thiosulfate solution (5.2.1.2.3) used for the titration ;m0is the mass, in grams, of the test portion (5.2.1.4.1) ;0,003545 is the mass, in grams, of chlorine (Cl2) corresponding to 1,00 ml of sodium thiosulfate solution,c(Na2S2O3.5H2O) = 0,1 mol/l ;c is the actual concentr
