1、BRITISH STANDARD BS ISO 11174:1996 Implementation of ISO 11174:1996 Workplace air Determination of particulate cadmium and cadmium compounds Flame and electro-thermal atomic absorption spectrometric method ICS 13.040.30BSISO 11174:1996 This British Standard, having been prepared under the direction
2、of the Health and Environment Sector Board, was published under the authority of the Standards Board and comes into effect on 15 January 1997 BSI 12-1998 The following BSI references relate to the work on this standard: Committee reference EH/2/2 Draft for comment 94/503110 DC ISBN 0 580 26876 4 Com
3、mittees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee EH/2, Air quality, to Subcommittee EH/2/2, Workplace atmospheres, upon which the following bodies were represented: Asbestos Information Centre Limited Asbestosis Research Coun
4、cil BCIRA British Ceramic Research Limited British Gas plc British Occupational Hygiene Society Chemical Industries Association Department of Trade and Industry (Laboratory of the Government Chemist) Employers Association of Catering Equipment Engineers Limited Engineering Equipment and Materials Us
5、ers Association Fibre Cement Manufacturers Association Limited Health and Safety Executive Institute of Energy Institute of Occupational Medicine Institution of Occupational Hygienists London Transport Royal Society of Chemistry Amendments issued since publication Amd. No. Date CommentsBSISO11174:19
6、96 BSI 12-1998 i Contents Committees responsible Inside front cover National foreword ii Foreword ii 1 Scope 1 2 Normative references 1 3 Principle 1 4 Reactions 2 5 Reagents 2 6 Apparatus 3 7 Sampling 5 8 Procedure for analysis 7 9 Expression of results 10 10 Special cases 12 11 Test report 13 Anne
7、x A (informative) Typical operating parameters for determination of cadmium by electrothermal atomic absorption spectrometry 14 Annex B (informative) Bibliography Inside back cover Table A.1 Typical temperature profile for determination of cadmium by electrothermal atomic absorption spectrometry 14
8、Table A.2 Typical autosampler injection volumes for the in situ preparation of matrix-modified reference and sample solutions 14BSISO11174-1996 ii BSI 12-1998 National foreword This British Standard reproduces verbatim ISO11174:1996 and implements it as the UK national standard. This British Standar
9、d is published under the direction of the Health and Environment Sector Board whose Technical Committee EH/2 has the responsibility to: aid enquirers to understand the text; present to the responsible international committee any enquiries on interpretation, or proposals for change, and keep UK inter
10、ests informed; monitor related international and European developments and promulgate them in the UK. NOTEInternational and European Standards, as well as overseas standards, are available from Customer Services, BSI, 389 Chiswick High Road, London W4 4AL. Textual errors. When adopting the text of t
11、he international standard, the textual errors listed below were discovered. They have been marked in the text and have been reported to ISO in a proposal to amend the text of the international standard. 1. Clause 6.1.4. The title should read “Portable flowmeter”. 2. Clause 6.2.9. The title should re
12、ad “Disposable gloves”. 3. Clause 8.2.2. The phrase with “partially cover with a watch” should read “partially cover with a watch glass”. 4. Clause 9.2.1. The term “spiked filters” should read “dosed filters” for consistency with 9.2.1. of BS 6069-3.8. A British Standard does not purport to include
13、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 i a
14、nd ii, theISO title page, page ii, pages 1 to 14, an inside back cover 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 theinside front cover.BS ISO 11174:1996 ii BSI 12-1998 Foreword ISO
15、(the International Organization 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 comm
16、ittee has been established 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 electrote
17、chnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75% of the member bodies casting a vote. International Standard ISO11174 was prepared by T
18、echnical Committee ISO/TC146, Air quality, Subcommittee SC2, Workplace atmospheres. Annexes A and B of this International Standard are for information only.BS ISO 11174:1996 BSI 12-1998 1 WARNING Cadmium and cadmium compounds are toxic and are suspected human carcinogens (see reference 1 in annexB).
19、 Avoid any exposure by inhalation. Personal protection (e.g. an effective respirator) must be used in all cases where exposure to cadmium or cadmium compounds is possible. 1 Scope This International Standard specifies a method for the determination of the mass concentration of particulate cadmium an
20、d cadmium compounds in workplace air, using either flame or electrothermal atomic absorption spectrometry. The sample digestion procedure specified in8.2.2 has been validated (see reference 2 in annex B) for a selection of cadmium compounds and pigments and glass enamels containing cadmium. The anal
21、ytical method has been validated (seereference 2 in annex B) for the determination of masses of 10ng to 600ng of cadmium per sample using electrothermal atomic absorption spectrometry, and 0,15g to 96g of cadmium per sample using flame atomic absorption spectrometry. The concentration range for cadm
22、ium in air for which this procedure is applicable is determined in part by the sampling procedure selected by the user. The method is applicable to personal sampling of the inhalable or respirable fraction of airborne particles, as defined in ISO7708, and to fixed-location sampling. 2 Normative refe
23、rences The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International S
24、tandard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 648:1977, Laboratory glassware One-mark pipettes. ISO 1042:1983, Laboratory glassware
25、 One-mark volumetric flasks. ISO 3585:1991, Borosilicate glass 3.3 Properties. ISO 3696:1987, Water for analytical laboratory use Specification and test methods. ISO 6955:1982, Analytical spectroscopic methods Flame emission, atomic absorption and atomic fluorescence Vocabulary. ISO 7708:1995, Air q
26、uality Particle size fraction definitions for health-related sampling. ISO 8655-1: 1) , Piston and/or plunger operated volumetric apparatus (POVA) Part 1: Definitions. ISO 8655-2: 1) , Piston and/or plunger operated volumetric apparatus (POVA) Part 2: Operating considerations. ISO 8655-3: 1) , Pisto
27、n and/or plunger operated volumetric apparatus (POVA) Part 3: Methods of test. ISO 8655-4: 1) , Piston and/or plunger operated volumetric apparatus (POVA) Part4:Specifications. ISO 8756:1994, Air quality Handling of temperature, pressure and humidity data. EN 482:1994, Workplace atmospheres General
28、requirements for the performance of procedures for the measurement of chemical agents. EN 1232: 1) , Workplace atmospheres Pumps for personal sampling of chemical agents Requirements and test methods. 3 Principle 3.1 Particulate cadmium and cadmium compounds are collected by drawing a measured volum
29、e of air through a filter mounted in a sampler designed to collect either the inhalable fraction of airborne particles or the respirable fraction of airborne particles, as appropriate (seenote17). 3.2 A test solution is prepared by treating the filter and collected sample with 5ml of nitric acid dil
30、uted1+1, heating on a hotplate until about 1ml of concentrated nitric acid solution remains, allowing the solution to cool and then diluting to10ml with water. 3.3 The test solution is analysed for cadmium by aspirating into the oxidizing air/acetylene flame of an atomic absorption spectrometer equi
31、pped with a cadmium hollow cathode lamp or electrodeless discharge lamp. Absorbance measurements are made at 228,8nm and results are obtained by the analytical-curve technique (seeISO6955:1982, subclause 6.1.1). 1) To be publishedBSISO 11174:1996 2 BSI 12-1998 3.4 For accurate determination when the
32、 concentration of cadmium in the solution is low, the analysis may be repeated using electrothermal atomic absorption spectrometry. Aliquots of the test solution and a matrix-modifier solution are injected onto a solid, pyrolytic graphite platform mounted in a pyrolytically coated graphite tube, and
33、 after the drying and sample ashing stages the sample is atomized electrothermally. Absorbance measurements are made at 228,8nm with background correction and results are obtained by the analytical-curve technique (see ISO6955:1982, subclause 6.1.1). 4 Reactions In general, the majority of particula
34、te cadmium compounds which are commonly found in samples of workplace air are converted to water-soluble cadmium ions (Cd 2+ ) by the sample digestion procedure specified in 8.2.2. However, if there is any doubt about the effectiveness of this procedure for digestion of particulate cadmium compounds
35、 which could be present in the test atmosphere, investigate this before proceeding with the method (see10.1). 5 Reagents During the analysis, use only reagents of analytical grade, and only water as specified in5.1. 5.1 Water, complying with the requirements for ISO3696 grade 2 water (electrical con
36、ductivity less than 0,1mS/m and resistivity greater than0,01MWm at 25C). 5.2 Nitric acid, (HNO 3 ), concentrated, r 1,42g/ml, 69% (m/m) to 71% (m/m). The concentration of cadmium shall be less than0,01g/ml. WARNING Concentrated nitric acid is corrosive and oxidizing, and nitric acid fumes are irrita
37、nt. Avoid exposure by contact with the skin or eyes, or by inhalation of fumes. Personal protective equipment (e.g. gloves, face shield or safety spectacles, etc.) must be used when working with the concentrated or diluted nitric acid, and concentrated nitric acid must be used in a fume hood. 5.3 Ni
38、tric acid, diluted 1 + 1. Carefully add 500ml of concentrated nitric acid(5.2) to 450ml of water (5.1) in a 2litre beaker. Swirl to mix, allow to cool and quantitatively transfer to a 1000ml one-mark volumetric flask(6.2.1.5). Dilute to the mark with water, stopper and mix thoroughly. 5.4 Nitric aci
39、d, diluted 1 + 9. Pour approximately 800ml of water (5.1) into a1000ml one-mark volumetric flask (6.2.1.5). Carefully add 100ml of concentrated nitric acid(5.2) to the flask and swirl to mix. Allow to cool, dilute to the mark with water, stopper and mix thoroughly. 5.5 Cadmium stock standard solutio
40、n, corresponding to 1000mg of Cd per litre. 5.5.1 Use a commercially available cadmium standard solution at a concentration of 1000mg/l. Observe the manufacturers expiry date or recommended shelf-life. Alternatively, prepare a cadmium standard solution according to the procedure specified in5.5.2. 5
41、.5.2 Accurately weigh 1,000g 0,001 g of cadmium metal, 99,9% (m/m) of Cd, into a 50ml beaker(6.2.1.1), add 20ml of the nitric acid diluted1+1 (5.3), cover with a watch glass (6.2.1.2) and heat to approximately 150C on the hotplate(6.2.4) in a fume hood until the metal is completely dissolved. Remove
42、 the beaker from the hotplate, allow to cool, quantitatively transfer the solution to a 1000ml one-mark volumetric flask(6.2.1.5), dilute to the mark with water (5.1), stopper and mix thoroughly. This solution may be stored in a polypropylene bottle (6.2.2) for up to one year. 5.6 Cadmium working st
43、andard solution A, corresponding to 100mg of Cd per litre. Using a pipette (6.2.1.3), accurately add 10,0ml of stock cadmium solution (5.5) to a 100ml one-mark volumetric flask (6.2.1.5). Add 1ml of concentrated nitric acid (5.2), dilute to the mark with water (5.1), stopper and mix thoroughly. This
44、 solution may be stored in a polypropylene bottle (6.2.2) for up to one month. 5.7 Cadmium working standard solution B, corresponding to 1mg of Cd per litre. Using a pipette (6.2.1.3), accurately add 100 l of cadmium stock solution (5.5) to a 100ml one-mark volumetric flask (6.2.1.5). Add 1ml of nit
45、ric acid(5.2), dilute to the mark with water (5.1), stopper and mix thoroughly. This solution may be stored in a polypropylene bottle (6.2.2) for up to one month.BS ISO 11174:1996 BSI 12-1998 3 5.8 Matrix-modifier solution, corresponding to 1g of Mg(NO 3 ) 2 6H 2 O per litre and 20g of NH 4 H 2 PO 4
46、per litre. Weigh 0,100g of magnesium nitrate hexahydrate Mg(NO 3 ) 2 6H 2 O and 2,00g of ammonium dihydrogen phosphate (NH 4 H 2 PO 4 ) into a 250ml beaker (6.2.1.1). Add 50ml of water (5.1) and swirl to dissolve. Add 10ml of concentrated nitric acid(5.2), swirl to mix, and quantitatively transfer t
47、he solution to a 100ml one-mark volumetric flask(6.2.1.5). Dilute to the mark with water, stopper and mix thoroughly. 5.9 Laboratory detergent solution, suitable for cleaning samplers and laboratory apparatus, diluted with water (5.1) according to the manufacturers instructions. 5.10 Air, compressed
48、 and filtered. 5.11 Acetylene, in a cylinder. 5.12 Argon, supplied in a cylinder or as a cryogenic fluid. NOTE 1This gas is only required if analysis is carried out by electrothermal atomic absorption spectrometry (see8.3.3.6). 6 Apparatus 6.1 Sampling equipment 6.1.1 Samplers, for collection of the
49、 inhalable fraction or the respirable fraction of airborne particles (see7.1.1) as defined in ISO7708, suitable for use with the cellulose ester membrane filters(6.1.2) and compatible with the sampling pumps (6.1.3) used. NOTE 2A number of different terms are used to describe samplers designed for collection of the inhalable fraction of airborne particles, for example, sampling heads, filter holders, filter cassettes and air monitoring cassettes. NOTE 3In general, the collection characteristics of inhalable
