1、BSI Standards PublicationBS EN ISO 13162:2015Water quality Determinationof carbon 14 activity Liquidscintillation counting method(ISO 13162:2011)BS EN ISO 13162:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO13162:2015. It is identical to ISO 13162:2011
2、.The UK participation in its preparation was entrusted to TechnicalCommittee EH/3, Water quality.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsi
3、ble for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 88660 7ICS 13.060.60; 17.240Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStand
4、ards Policy and Strategy Committee on 31 August 2015.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 13162 August 2015 ICS 17.240; 13.060.60 English Version Water quality - Determination of carbon 14 activity - Liquid scintillation counti
5、ng method (ISO 13162:2011) Qualit de leau - Dtermination de lactivit volumique du carbone 14 - Mthode par comptage des scintillations en milieu liquide (ISO 13162:2011) Wasserbeschaffenheit - Bestimmung der Aktivitt von Kohlenstoff-14 - Verfahren mit dem Flssigszintillationszhler (ISO 13162:2011) Th
6、is European Standard was approved by CEN on 30 July 2015. 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. Up-to-date lists and bibliographical referenc
7、es 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 translation under the responsibility of a CEN me
8、mber 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, Finland, Former Yugoslav Republic of Macedonia, F
9、rance, 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 STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES
10、 KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 13162:2015 EBS EN ISO 13162:2015EN ISO 13162:2015 (E) 3 European foreword The text of ISO
11、 13162:2011 has been prepared by Technical Committee ISO/TC 147 “Water quality” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 13162:2015 by Technical Committee CEN/TC 230 “Water analysis” the secretariat of which is held by DIN. This European Standard
12、shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2016, and conflicting national standards shall be withdrawn at the latest by February 2016. Attention is drawn to the possibility that some of the elements of thi
13、s 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 this European Stan
14、dard: 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, Slovakia, Slovenia, Sp
15、ain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 13162:2011 has been approved by CEN as EN ISO 13162:2015 without any modification. BS EN ISO 13162:2015ISO 13162:2011(E) ISO 2011 All rights reserved iiiContents PageForeword ivIntroduction . v1 Scope 12 Norm
16、ative references .13 Symbols, definitions, units, and abbreviations .24 Principle .25 Reagents and equipment 35.1 Reagents 35.2 Equipment .46 Sampling and samples .56.1 Sampling 56.2 Sample storage 57 Procedure 57.1 Sample preparation .57.2 Preparation of the sources to be measured .57.3 Counting pr
17、ocedure 67.4 Calibration and verification 67.5 Measurement conditions .68 Expression of results .78.1 General .78.2 Calculation of activity concentration .78.3 Decision threshold 88.4 Detection limit 88.5 Confidence limits .98.6 Calculations using the activity per mass 99 Test report .9Annex A (info
18、rmative) Numerical applications .11Annex B (informative) Internal standard method .13Annex C (informative) Extraction of total carbon: precipitate counting 15Annex D (informative) Extraction of total carbon: absorption counting .18Bibliography .21BS EN ISO 13162:2015ForewordISO (the International Or
19、ganization for Standardization) is a worldwide federation of national 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 establ
20、ished has the right to be represented on that committee. International 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 standardizati
21、on.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. P
22、ublication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.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 paten
23、t rights.ISO 13162 was prepared by Technical Committee ISO/TC 147, Water quality.ISO 13162:2011(E)iv ISO 2011 All rights reservedBS EN ISO 13162:2015IntroductionThe carbon 14 (14C) present in the environment is of natural origin and man made. As a result of atmospheric nuclear weapon testing, emissi
24、ons from nuclear engineering installations, and the application and processing of isotopes, relatively large amounts of 14C have been released into the environment. Due to the substantial proportion of 14C in the human internal dose contribution, monitoring of 14C activity concentrations in the envi
25、ronment is necessary in order to follow its circulation in the hydrosphere and biosphere. 14C is the second radionuclide (null3 500 Bq) to contribute to the human body natural radioactivity, behind 40K (null6 000 Bq).ISO 13162:2011(E) ISO 2011 All rights reserved vBS EN ISO 13162:2015BS EN ISO 13162
26、:2015INTERNATIONAL STANDARD ISO 13162:2011(E)Water quality Determination of carbon 14 activity Liquid scintillation counting methodWARNING Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problem
27、s, if any, associated with its use. It is the responsibility 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 according to this International Standard be carried
28、 out by suitably trained staff.1 ScopeThis International Standard specifies the conditions for the determination of 14C activity concentration in samples of environmental water or of 14C-containing water using liquid scintillation counting.The method is applicable to the analysis of any organic mole
29、cule soluble in water that is well mixed with the scintillation cocktail. It does not apply to micelles or “large” particles (lipids, fulvic acid, humic acid, etc.) that are inadequately mixed with the scintillation cocktail and the water. Some beta energy is lost without any excitation of the scint
30、illation cocktail and the results are underestimated. The method is not applicable to the analysis of organically bound 14C, whose determination requires additional chemical processing (such as chemical oxidation, combustion).It is possible to determine 14C activity concentrations below 106Bq lnull1
31、without any sample dilution.2 Normative referencesThe 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 document (including any amendments) applies.
32、ISO 5667-1, Water quality Sampling Part 1: Guidance on the design of sampling programmes and sampling techniquesISO 5667-3, Water quality Sampling Part 3: Preservation and handling of water samplesISO 11929, Determination of the characteristic limits (decision threshold, detection limit and limits o
33、f the confidence interval) for measurements of ionizing radiation Fundamentals and applicationISO/IEC 17025, General requirements for the competence of testing and calibration laboratoriesISO 80000-10, Quantities and units Part 10: Atomic and nuclear physicsISO/IEC Guide 98-3:2008, Uncertainty of me
34、asurement Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) ISO 2011 All rights reserved 1BS EN ISO 13162:20153 Symbols, definitions, units, and abbreviationsFor the purposes of this document, the symbols, definitions, units, and abbreviations defined in ISO 80000-10, ISO 1192
35、9, ISO/IEC Guide 98-3 and the following apply.null Activity of the calibration source, in becquerelsnullnullActivity concentration, in becquerels per litrecA*Decision threshold, in becquerels per litrecAnullDetection limit, in becquerels per litreccAAtrianglerighttriangleleftnullLower and upper limi
36、ts of the confidence interval, in becquerels per litrenullqQuench factornull Mass of test sample, in kilogramsnull0Background count rate, in reciprocal secondsnullgSample count rate, in reciprocal secondsnullsCount rate of the calibration sample, in reciprocal secondsnull0Background counting time, i
37、n secondsnullgSample counting time, in secondsnullsCounting time of the calibration sample, in secondsnull Expanded uncertainty, calculated by null null nullnullnull(nullnull) with null null 1, 2, , in becquerels per litrenull(nullnull) Standard uncertainty associated with the measurement result, in
38、 becquerels per litrenull Volume of test sample, in litresnull Activity per mass, in becquerels per kilogramnullmaxMaximum energy for the beta emission, in kiloelectronvoltsnull Detection efficiencynull Mass density of the sample, in kilograms per litre4 PrincipleThe scintillation phenomenon results
39、 from interaction of ionizing radiation with solvents and compounds exhibiting fluorescence (scintillators). Both solvents and scintillators constitute the scintillation cocktail. The scintillation mixture is achieved by adding the scintillation cocktail to the test sample in order to obtain a homog
40、eneous mixture.The test sample is mixed with the scintillation cocktail in a counting vial to obtain a homogeneous medium. Electrons emitted by 14C transfer their energy to the scintillation medium. Molecules excited by this process return to their ground state by emitting photons that are detected
41、by photodetectors.The electric pulses emitted by the photodetectors are amplified, sorted (in order to remove random events) and analysed by the electronic systems and the data analysis software. The count rate of these electric pulses allows the determination of the test sample activity, after corr
42、ecting for the background count rate and detection efficiency.ISO 13162:2011(E)2 ISO 2011 All rights reservedBS EN ISO 13162:2015In order to determine the background, a blank sample is prepared in the same way as the test sample. The blank sample is prepared using a reference water of the lowest act
43、ivity available, in accordance with the activities to be measured.The detection efficiency is determined with a calibration sample that is prepared with a standard of aqueous 14C, or a dilution of this standard with reference water, measured under the same conditions as the test sample.The sample (b
44、lank, test, calibration) and the measurement conditions shall be: same type of counting vial; same filling geometry; same scintillation cocktail; same ratio between test sample and scintillation cocktail; temperature stability of the detection apparatus; value of quench-indicating parameter included
45、 in calibration curve.A prerequisite for the direct determination of 14C in a water sample is the absence of or a negligible contribution from other beta-emitting radionuclides, such as 90Sr and Ra isotopes. When the radionuclide content of the sample is unknown, the method specified in this Interna
46、tional Standard only provides a 14C equivalent activity for the sample.Examples of methods of sample pretreatment are described in Annexes C and D.Concerning quench correction, if particular conditions of chemical quenching affect the measurement results, it is recommended that a quench curve be est
47、ablished. It is important to choose the chemical quenching agent in accordance with the supposed type of quenching observed in the sample.5 Reagents and equipment5.1 ReagentsDuring the analysis, unless otherwise stated, use only reagents of recognized analytical grade.5.1.1 Reference water for the b
48、lankThe reference water for the blank should be as free as possible of chemical or radioactive impurities.The reference water may have a low 14C activity concentration, in becquerels per litre, at the time null at which the samples are measured.For example, obtain water with a 14C activity concentra
49、tion as low as possible, e.g. (deep) subterranean water. Distil the water. Keep the distillate in a well-sealed borosilicate glass bottle in the dark at a temperature as constant as possible; this reference water shall be kept physically remote from any 14C-containing material (see next paragraph). Determine (see final paragraph) the 14C activity concentration (null null 0), in becquerels per litre, of this water and note the date (null null 0) of this determination.It is advisable to keep an adequate quantity of reference w
