1、DRAFT FOR DEVELOPMENT DD ENV 12908:1998 Lead and lead alloys Analysis by Optical Emission Spectrometry (OES) with spark excitation The European Standard ENV 12908:1998 has the status of a British Standard ICS 77.120.60DDENV12908:1998 This Draft for Development, having been prepared under the directi
2、on of the Engineering SectorBoard, was published underthe authority of the Standards Board and comes intoeffect on 15February1998 BSI 03-1999 ISBN 0 580 29030 1 National foreword This Draft for Development is the English language version of ENV12908:1998 published by the European Committee for Stand
3、ardization (CEN). The UK participation in its preparation was entrusted to Technical Committee NFE/22, Lead and lead alloys, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or prop
4、osals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement inter
5、national or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to incl
6、ude all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages
7、 i and ii, theENV title page, pages 2 to 7 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsDDENV12908:199
8、8 BSI 03-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of ENV 12908 3ii blankEUROPEAN PRESTANDARD PRNORME EUROPENNE EUROPISCHE VORNORM ENV 12908 November 1997 ICS 77.120.60 Descriptors: Lead, lead alloys, chemical analysis, analysis methods, optical emission spectrometry
9、English version Lead and lead alloys Analysis by Optical Emission Spectrometry (OES) with spark excitation Plomb et alliages de plomb Analyse par Spectromtrie dEmission Optique (OES) avec excitation par tincelles Blei und Bleilegierungen Analyse durch Optische Emissionsspektrometrie (OES) mit Funken
10、anregung This European Prestandard (ENV) was approved by CEN on 29 October 1997 as a prospective standard for provisional application. The period of validity of this ENV is limited initially to three years. After two years the members of CEN will be requested to submit their comments, particularly o
11、n the question whether the ENV can be converted into a European Standard. CEN members are required to announce the existence of this ENV in the same way as for an EN and to make the ENV available promptly at national level in an appropriate form. It is permissible to keep conflicting national standa
12、rds in force (in parallel to the ENV) until the final decision about the possible conversion of the ENV into an EN is reached. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherland
13、s, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1997 CEN All rights of exploitation in any form and by any means reser
14、ved worldwide for CEN national Members. Ref. No. ENV 12908:1997 EENV12908:1997 BSI 03-1999 2 Foreword This European Prestandard has been prepared by Technical Committee CEN/TC306 “Lead and lead alloys”, the secretariat of which is held by AFNOR. Within its programme of work, CEN/TC306 requested CEN/
15、TC306/GT3 “Lead and lead alloys Sampling and analysis” to prepare the following prestandard: ENV 12908, Lead and lead alloys Analysis by optical emission spectrometry (OES) with spark excitation. WARNING: Any hazards involved in handling and use of lead and lead alloys are detailed in the suppliers
16、health and safety data sheet. All relevant precautions shall be taken to protect personnel. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to announce this European Prestandard: Austria, Belgium, Czech Republic, Denmark, F
17、inland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Principle 3 5 Apparatus 3 6 Sampling 3 7 Procedure 4 8 Expression of r
18、esults 5 9 Test report 5 Annex A (informative) Lead and lead alloys Wavelengths commonly used for spectrometric analysis 6 Table 1 Elements Ranges of application 3 Table A.1 Wavelengths commonly used forspectrometry analysis 6ENV12908:1997 BSI 03-1999 3 1 Scope This prestandard specifies the method
19、for the analysis of lead and lead alloys by optical emission spectrometry (OES) with spark excitation. The method is applicable to the elements and ranges given inTable 1: Table 1 Elements Ranges of application 2 Normative references This European Prestandard incorporates by dated or undated referen
20、ce, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Prestandard only when incorpor
21、ated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. prEN 12402, Lead and lead alloys Methods of sampling for analysis. 3 Definitions For the purposes of this prestandard, the following definitions apply: 3.1 Certified Reference Mater
22、ial (CRM) material whose relevant analysis is known to a high degree of accuracy and element contents of which have been certified by numerous chemical analyses performed by several independant laboratories, followed by statistical analysis of all the results obtained NOTEThe method of chemical anal
23、ysis used to analyse a CRM should conform to an International, European or National standard. 3.2 Reference Material (RM) material whose relevant analysis has been accurately determined by chemical methods, but which has only been analysed by one or more laboratories and which has not been certified
24、 NOTEThe method of chemical analysis used to analyse an RM should conform to an International, European or National standard. 3.3 drift control samples these samples are a series of homogeneous discs that contain all the elements which have been calibrated, at both near zero concentration and high c
25、oncentrations near the top of the calibration ranges NOTENo analyses are necessary on these discs. These discs are measured during the calibration. The intensities obtained are stored in the computer. 3.4 sample portion of the lead or lead alloy representative of the chemical composition 4 Principle
26、 The sample is quantitatively analysed by measuring the intensity of the element specific radiation generated by the spark resulting from the application of a high voltage between the sample, as one electrode, and an inert counter-electrode. The intensity measured is compared with the element calibr
27、ation and converted to a percentage. 5 Apparatus 5.1 Optical emission spectrometer Spectrometer with spark excitation that shall be able to measure the intensity of the optical radiation emitted at specific wavelenghts by the elements present in the material. The wavelengths generally used are given
28、 inAnnex A (informative). 5.2 Machine for sample surface preparation The lathe or milling machine used for surface preparation shall be able to produce a surface that conforms to the requirements of7.2. 6 Sampling Sampling shall be carried out in accordance with prEN12402 Elements Ranges of applicat
29、ion % (m/m) Ag Al As Bi Ca Cd Cu Ni S Sb Se Sn Te Zn 0,0002 to 0,3 0,001 to 0,04 0,0005 to 0,3 0,0005 to 0,2 0,0005 to 0,2 0,0002 to 0,2 0,0002 to 0,1 0,0002 to 0,01 0,001 to 0,01 0,0005 to 15 0,001 to 0,04 0,0005 to 15 0,0005 to 0,05 0,0002 to 0,01ENV12908:1997 4 BSI 03-1999 7 Procedure 7.1 Trainin
30、g of personnel All personnel carrying out the analysis shall be fully trained in the steps detailed below. 7.2 Surface preparation WARNING: The appropriate safety recommendations for the use of mechanical apparatus should be observed. These operations should be carried only by properly trained perso
31、nnel wearing appropriate personal protective equipment. 7.2.1 The surface of the sample shall be prepared, by turning or milling, to a surface finish that is sufficiently plane and smooth so as not to affect the analytical results. Once a method of preparation is chosen, whether turning or milling,
32、the same method shall be used for all samples, reference materials and certified reference materials to avoid variations in the surface finish which may affect the analysis. To avoid cross contamination between different materials, for example pure lead and lead alloys, all relevant components of th
33、e machine shall be thoroughly cleaned before use. Once the surface has been prepared, it shall be kept clean to avoid any contamination, for example fingerprints. NOTEMeasurements should be carried out as soon as possible after any surface preparation. 7.2.2 The minimum thickness of metal removed sh
34、all be1mm to eliminate any contamination. 7.2.3 The turning or milling shall be carried out at a suitable rate that avoids undue heating of the sample as this may cause changes in the sample and lead to variations in the analysis. Lubricant shall not be used. 7.3 Calibration 7.3.1 Method of calibrat
35、ion The original calibration of the spectrometer is carried out by using a range of reference materials to prepare calibration graphs from which the analysis of unknown samples is obtained. The calibrations are usually stored within a computer integral to the spectrometer. The calibration shall be i
36、n accordance with the spectrometer manufacturers instruction manual, using the appropriate certified reference materials, if they exist. If no certified reference materials are available, reference materials with an accurate analysis shall be used. 7.3.2 Drift correction Any drift from the original
37、calibration is corrected periodically by the use of drift control samples in accordance with the spectrometer manufacturers instruction manual. 7.3.3 Recalibration To ensure the continuing validity of an element calibration, the zero, top and two others points in the calibration shall be checked per
38、iodically using CRMs, and/or the RMs. A drift correction operation shall be carried out immediately prior to these checks to ensure optimum setting of the instrument. If any significant error is found, the calibration (see7.3.1) shall be repeated. 7.3.4 Range of calibration The range of calibration
39、for an element shall extend well above the element content of the sample with the highest percentage, unless unavoidable heterogeneity makes the preparation of reference materials for the higher percentage impossible. 7.3.5 Number of sparks on calibration materials The number of sparks carried out o
40、n a reference material for calibration shall not be less than six. The sparks shall be evenly distributed over the prepared surface. All intensity measurements shall be examined; if any intensity measurement is obviously aberrant, further sparks shall be carried out to obtain the minimum six accepta
41、ble measurements. The average of the six acceptable measurements is used for calibration. 7.4 Analysis 7.4.1 Analysis of samples The method used shall be in accordance with the spectrometer manufacturers instruction manual. 7.4.2 Number of sparks on samples The number of sparks carried out on a samp
42、le shall not be less than three. The sparks shall be evenly distributed over the prepared surface. All percentages resulting from measurements shall be examined; if any measurement is obviously aberrant, further sparks shall be carried out to obtain the minimum of three acceptable measurements.ENV12
43、908:1997 BSI 03-1999 5 8 Expression of results 8.1 Results For each element the average of the acceptable percentages represents the final result. 8.2 Rounding of analysis results In expressing the final results, the values obtained shall be rounded according the following rules: a) if the figure im
44、mediately after the last figure to be retained is less than five, the last figure to be retained shall be kept unchanged; b) if the figure immediately after the last figure to be retained is equal to or greater than five, the last figure to be retained shall be increased by one. 8.3 Precision NOTEIn
45、 accordance with the status of a prestandard, precision data will be included when the results of the precision tests are available. 9 Test report The test report shall include the following information: a) name of the laboratory; b) identification of the sample; c) results of the analysis; d) date
46、of the analysis; e) reference number of this prestandard (ENV12908); f) signature of the laboratory manager or other responsible person. However, if the certificates are prepared by a suitable data processing system, the signature may be replaced by an indication of the name and the position of the
47、person responsible for validating the document.ENV12908:1997 6 BSI 03-1999 Annex A (informative) Lead and lead alloys Wavelengths commonly used for spectrometric analysis A.1 Introduction The list of wavelengths inTable A.1 has been condensed from the15replies received to a questionnaire sent to spe
48、ctrometer users in the European lead industry. The table is not exhaustive: the exclusion of a line does not have any significance. The table gives: the wavelengths of lines in use; approximate consensus of the lower and upper practical application limits for the line as reported in the questionnair
49、es, and; the number of users of each wavelength. The lower limits quoted are normally attained using the maximum practical sensitivity available on the spectrometer. For some elements, where the maximum limit quoted also covers alloys, the maximum value can only be obtained by decreasing the sensitivity of the spectrometer having the effect of a deterioration of the lower limit. Table A.1 Wavelengths commonly used for spectrometry analysis Element Symbol Wavelength Approximate Limits Number of users nm Low % (m/m) High % (m
