BS EN ISO 7027-1-2016 Water quality Determination of turbidity Quantitative methods《水质 浊度的测定 测算方法》.pdf

1、BS EN ISO 7027-1:2016W a t e r q u a l i t y D e t e r m i n a t i o nof turbidityPart 1: Quantitative methods (ISO7027-1:2016)BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN ISO 7027-1:2016 BRITISH STANDARDNational forewordThis British Standard is the UK imple

2、mentation of EN ISO7027-1:2016. It supersedes BS EN ISO 7027:2000 which iswithdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee EH/3/2, Physical chemical and biochemical methods.A list of organizations represented on this committee can beobtained on request to its sec

3、retary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 81961 2ICS 13.060.60Compliance with a British Standard cannot

4、confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 July 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 7027-1 June 2

5、016 ICS 13.060.60 Supersedes EN ISO 7027:1999English Version Water quality - Determination of turbidity - Part 1: Quantitative methods (ISO 7027-1:2016) Qualit de leau - Dtermination de la turbidit - Partie 1: Mthodes quantitatives (ISO 7027-1:2016) Wasserbeschaffenheit - Bestimmung der Trbung - Tei

6、l 1: Quantitative Verfahren (ISO 7027-1:2016) This European Standard was approved by CEN on 15 April 2016. 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 alterati

7、on. 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

8、 translation 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,

9、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, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZ

10、ATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 7027-1:2016 EBS EN ISO 7027-1:2016EN ISO

11、7027-1:2016 (E) 3 European foreword This document (EN ISO 7027-1:2016) has been prepared by Technical Committee ISO/TC 147 “Water quality” in collaboration with Technical Committee CEN/TC 230 “Water analysis” the secretariat of which is held by DIN. This European Standard shall be given the status o

12、f a national standard, either by publication of an identical text or by endorsement, at the latest by December 2016, and conflicting national standards shall be withdrawn at the latest by December 2016. This document supersedes EN ISO 7027:1999. Attention is drawn to the possibility that some of the

13、 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 the following countries are bound to implement th

14、is European Standard: 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, Netherlands, Norway, Poland, Portugal, Romania, Slovak

15、ia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 7027-1:2016 has been approved by CEN as EN ISO 7027-1:2016 without any modification. BS EN ISO 7027-1:2016ISO 7027-1:2016(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms

16、and definitions . 14 Sampling and samples 25 Quantitative methods of turbidity measurement using optical nephelometers and turbidimeters . 25.1 General principles 25.2 Reagents 35.3 Measurement of diffuse radiation (nephelometry) 55.3.1 Apparatus . 55.3.2 Calibration . 55.3.3 Procedure . 55.3.4 Expr

17、ession of results 55.3.5 Test report . 55.4 Measurement of attenuated radiation (turbidimetry) . 55.4.1 Apparatus . 55.4.2 Calibration . 65.4.3 Procedure . 65.4.4 Expression of results 65.4.5 Test report . 6Annex A (informative) Results of an interlaboratory collaborative trial to evaluate the suita

18、bility of a synthetic polymer for use as a secondary standard to formazin in turbidity measurements 7Bibliography 9 ISO 2016 All rights reserved iiiContents PageBS EN ISO 7027-1:2016ISO 7027-1:2016(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of nation

19、al standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. Internatio

20、nal organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended

21、for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.

22、org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will

23、be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressio

24、ns related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 2, Phys

25、ical, chemical and biochemical methods.This first edition of ISO 7027-1, together with ISO 7027-2, cancels and replaces ISO 7027:1999, which has been technically revised. ISO 7027 consists of the following parts, under the general title Water quality Determination of turbidity: Part 1: Quantitative

26、methodsThe following part is under preparation: Part 2: Semi-quantitative methodsiv ISO 2016 All rights reservedBS EN ISO 7027-1:2016ISO 7027-1:2016(E)IntroductionMeasurements of turbidity can be affected by the presence of dissolved light-absorbing substances (substances imparting colour). Such eff

27、ects can be minimized, however, by performing measurements at wavelengths greater than 800 nm. Only carbon black and a blue colour, which can be found in certain polluted waters, slightly affects measurements of turbidity in this region of the spectrum. Air bubbles can also interfere with measuremen

28、ts, but such interference can be minimized by careful handling of the samples.It is to be investigated whether and to what extent, particular problems will require the specification of additional marginal conditions. ISO 2016 All rights reserved vBS EN ISO 7027-1:2016BS EN ISO 7027-1:2016Water quali

29、ty Determination of turbidity Part 1: Quantitative methodsWARNING Persons using this International Standard should be familiar with normal laboratory practice. This International Standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibilit

30、y of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.IMPORTANT It is absolutely essential that tests conducted in accordance with this International Standard be carried out by suitably qualified staff.1 ScopeThis part of

31、ISO 7027 specifies two quantitative methods using optical turbidimeters or nephelometers for the determination of turbidity of water:a) nephelometry, procedure for measurement of diffuse radiation, applicable to water of low turbidity (for example drinking water);b) turbidimetry, procedure for measu

32、rement of the attenuation of a radiant flux, more applicable to highly turbid waters (for example waste waters or other cloudy waters).Turbidities measured according to the first method are presented as nephelometric turbidity units (NTU). The results typically range between 0,05 NTU and 400 NTU. De

33、pending on the instrument design, it can also be applicable to waters of higher turbidity. There is numerical equivalence of the units NTU and formazin nephelometric unit (FNU).Turbidity measured by the second method is expressed in formazin attenuation units (FAU), results typically range between 4

34、0 FAU and 4 000 FAU.2 Normative referencesThe 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 (

35、including any amendments) applies.CIE Publication No. 17, International Lighting Vocabulary3 Terms and definitionsFor the purposes of this document, the terms and definitions given in CIE Publication No. 17 and the following apply.3.1turbidityreduction of transparency of a liquid caused by the prese

36、nce of undissolved matterINTERNATIONAL STANDARD ISO 7027-1:2016(E) ISO 2016 All rights reserved 1BS EN ISO 7027-1:2016ISO 7027-1:2016(E)4 Sampling and samplesMaintain all containers that come into contact with the sample in a scrupulously clean condition. Wash with hydrochloric acid or surfactant cl

37、eaning solution.Collect samples in glass or plastics bottles and carry out the determinations, as soon as possible after collection. If storage is unavoidable, store the samples in a cool, dark room but for not longer than 24 h. If the samples have been stored under cool conditions, allow them to co

38、me to room temperature before measurement. Prevent contact between the sample and air and avoid unnecessary changes in the temperature of the sample.5 Quantitative methods of turbidity measurement using optical nephelometers and turbidimeters5.1 General principlesA water sample coloured by dissolved

39、 substances is a homogeneous system that only attenuates radiation passing through the sample. A water sample containing undissolved substances attenuates the incident radiation and in addition the insoluble particles which are present diffuse the radiation unequally in all directions. The forward d

40、iffusion of radiation by the particles affects the attenuation so that the common spectral attenuation coefficient () is the sum of the spectral diffusion coefficient s() and the spectral absorption coefficient (): () () ()=+s (1)To obtain the spectral diffusion coefficient s() alone, the spectral a

41、bsorption coefficient () needs to be known. In order to determine the spectral absorption coefficient of the dissolved substance, the undissolved substances can, in some cases, be removed by filtration, but this may cause interferences. Therefore, it is necessary to report the results of the determi

42、nation of turbidity in comparison to a calibration standard.The intensity of the diffuse radiation depends upon the wavelength of the incident radiation, the measurement angle, and the shape, optical characteristics and particle size distribution of the particles suspended in the water.In measuremen

43、ts of the attenuation of transmitted radiation, the measured value depends upon the aperture angle 0of the radiant efficiency arriving at the receiver.When measuring the diffuse radiation, the measured values depend upon the angle and the aperture angle . The angle is that enclosed by the direction

44、of the incident radiation and the direction of the measured diffuse radiation (see Figure 1).2 ISO 2016 All rights reservedBS EN ISO 7027-1:2016ISO 7027-1:2016(E)0Key1 light sourceFigure 1Application of the measurement of the concentration of undissolved substances would be possible only if the para

45、meters identified above were known. In general, this information is not available, so the mass concentration of the suspended particles cannot be calculated from the value of turbidity.NOTE 1 Instrument-to-instrument comparisons are possible only if apparatus is used in accordance with this part of

46、ISO 7027 and the same measuring principle is applied.NOTE 2 The Jackson candle turbidimeter was originally the standard instrument for turbidity measurements. In general, Jackson turbidity units (JTU) cannot be related to other turbidity units.5.2 ReagentsUse only reagents of recognized analytical g

47、rade. Reagents prepared in accordance with this part of ISO 7027 can be stored in hard glass, high-density polyethylene (HDPE) or low-density polyethylene (LDPE) bottles respectively.5.2.1 Water, for the preparation of the formazin stock and reference suspensions.Soak a membrane filter of pore size

48、0,45 m for 1 h in 100 ml of distilled water. Filter 250 ml of distilled water through it and discard the water. Then pass a two-litre volume of distilled water twice through the membrane and reserve this water for the preparation of the formazin suspensions. Other particle free waters like reverse o

49、smosis water can be used instead.5.2.2 Formazin (C2H4N2)x, stock suspension I (4 000 FNU).Suspensions with 4 000 FNU (NTU) are commercially available. Their use is recommended. They are available from numerous sources. Possible health hazards arising from the toxicity and carcinogenicity of hydrazine sulfate used for preparing the standard on the bench can be avoided.From some manufacturers, specific stabilized formazin suspensions are available.1)These commercially available suspensions may be stable for up to one year