1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI British StandardsWB9423_BSI_StandardColCov_noK_AW:BSI FRONT COVERS 5/9/08 12:55 Page 1Use of the Ringelmann and miniature smoke chartsBS 2742:2009BS 2742:2009 BRITISH STANDARDPublishing and copyright
2、 informationThe BSI copyright notice displayed in this document indicates when the document was last issued. BSI 2009 ISBN 978 0 580 62300 4 ICS 13.040.40, 91.060.40 The following BSI references relate to the work on this standard: Committee reference EH/2 Draft for comment 08/30179078 DCPublication
3、 historyFirst published March 1958First revision December 1969Second (present) edition, May 2009Amendments issued since publicationDate Text affected BRITISH STANDARD BSI 2009 iBS 2742:2009ContentsForeword iiIntroduction 11 Scope 12 Normative references 23 Use of the Ringelmann chart and miniature s
4、moke chart 2AnnexesAnnex A (informative) Format of Ringelmann charts 4Annex B (informative) Chart holders and use of the chart BS 2742C 5Bibliography 7List of figuresFigure B.1 Suitable holder for BS 2742C Ringelmann chart 5Figure B.2 Sketch showing method of use of British Standard Ringelmann chart
5、 6Figure B.3 Suitable holder for BS 2742M miniature smoke chart 6Summary of pagesThis document comprises a front cover, an inside front cover, pages i to ii, pages 1 to 8, an inside back cover and a back cover.BS 2742:2009ii BSI 2009BRITISH STANDARDForewordPublishing informationThis British Standard
6、 is published by BSI and came into effect on 31 May 2009. It was prepared by Subcommittee EH/2/1, Stationary source emission, under the authority of Technical Committee EH/2, Air quality. A list of organizations represented on this committee can be obtained on request to its secretary.SupersessionTh
7、is British Standard supersedes BS 2742:1969, which is withdrawn.Relationship with other publicationsThis British Standard is intended to be used with either of two charts: BS 2742C, Ringelmann chart or BS 2742M, Miniature smoke chart.Information about this documentThis is a full revision of the stan
8、dard, and introduces the following principal changes: the 1972 Addendum has been removed: when it was developed, it was subject to uncertainty and in practice only should have only been applied to a limited number of coal burning chain grate stoker appliances (which are now rare); the relationship w
9、as not truly applicable to other firing methods or fuels as the particles emitted are of a different particle size distribution and reflectance; added description of the manufacture/form of BS 2742C, Ringelmann chart and BS 2742M, Miniature smoke chart; this revision does not alter the technical req
10、uirements from those stated in the 1958 and 1969 editions; the values, however, are now expressed in metric terms.Presentational conventionsThe provisions in this standard are presented in roman (i.e. upright) type. Its recommendations are expressed in sentences in which the principal auxiliary verb
11、 is “should”.Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible fo
12、r its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.BRITISH STANDARD BSI 2009 1BS 2742:2009IntroductionThe method of visual assessment of smoke emission by comparison of the darkness of the smoke with standard shades of grey on a chartplaced in
13、a suitable position was devised by Professor Ringelmann of Paris in 1898. Professor Ringelmann obtained the shades of grey bycross-hatching in black on a white background so that a knownpercentage of the white was obscured. In use, the charts were placedat such a distance from the observer that the
14、black lines merged intothe white background and produced for each shade, apparently, auniform grey. The numbers of the shades (the Ringelmann numbers)ranged from 0 (white) to 5 (black), the stages being by changes of 20% in obscuration of the background. The original charts were oflarge size so that
15、 the accuracy of reproduction could be obtained in adrawing office; since that time various other methods of reproductionhave been tried and the size and details of the chart have beenmodified by various authorities from time to time.Actually, Professor Ringelmanns original chart cannot have beendra
16、wn with 100% black ink on 100% white paper, since neither wasobtainable. The commercially-printed charts in use for many years,including those issued by the U.S. Bureau of Mines, were printed onpaper with a luminance factor of about 80%, with ink of luminancefactor about 5%. Measurements on smoke wh
17、ich are accepted arederived from the use of commercially-printed Ringelmann charts, andtherefore the British Standard Ringelmann chart, BS 2742C, whichhas been so printed as to reproduce with consistency shades of greywhich are near the average of those to which users are accustomed.For convenience
18、in size, the British Standard charts comprise the fiveshades corresponding to Nos. 0 to 4 Ringelmann; the black strip wasincluded only for control during printing. A brief description of theconstruction of the British Standard Ringelmann chart, BS 2742C, is inAnnex A. Annex B shows example chart hol
19、ders and a sketch of thechart in use.1 ScopeThis British Standard provides guidance on the use of BS Ringelmanncharts to assess smoke emissions from unregulated processes. It is notsuitable for calibrating Continuous Emissions Monitoring Systems. Itis not applicable to processes whose emissions are
20、regulated by EUDirectives with stated Uncertainty.NOTE Most regulated processes have particulate emissions limits belowRingelmann 1.This British Standard is intended for use with the related publications: BS 2742C, Ringelmann chart; BS 2742M, Miniature smoke chart.Other measuring devices or charts a
21、re not suitable for use withthis British Standard.BS 2742:20092 BSI 2009BRITISH STANDARD2 Normative referencesThe following referenced documents are indispensable for theapplication of this document. For dated references, only the editioncited applies. For undated references, the latest edition of t
22、hereferenced document (including any amendments) applies.BS 2742C, Ringelmann chartBS 2742M, Miniature smoke chart3 Use of the Ringelmann chart and miniaturesmoke chart3.1 Ringelmann chart, BS 2742C3.1.1 Before useThe chart should be mounted so as to be held firmly without creasesor bending. The por
23、tion of any holder adjoining the “viewing edge”of the chart should be neutral in colour: aluminium is a suitable ma-terial (a suitable form of holder is shown in Figure B.1). Protectivecoverings should not be applied to the chart in use. If the chart isattached to a board or other support, the fixin
24、g medium should notimpair the luminance of the working surface of the chart.3.1.2 Using the Ringelmann chart The chart should be used under daylight conditions and held or fixedfacing the observer in a vertical plane (e.g. as shown in Figure B.2).Where possible, the chart should be in line with the
25、top of the chim-ney and placed so that the chart and the smoke have a similar skybackground. The chart should be at a sufficient distance from theobserver for the lines to appear to merge until each square forms auniform shade. For most observers, this distance is in excess of 15 m.Observations shou
26、ld be carried out as far as practicable under condi-tions of uniform general illumination from the sky, but if observationsare made with the sun shining, or with the sky bright on one side, thebright source of illumination should be approximately at right-angles to the line of vision, and not in fro
27、nt of or behind theobserver. The white (No. 0) square provides a useful indication of theillumination and will reveal any overshadowing or uneven illuminationof the chart. It also facilitates the detection of rainspotting or othersoiling of the chart. Under hazy conditions, readings should not be ta
28、ken at extreme distances, as there is a tendency for the readingsto be low.The angle of view of the chart and smoke should be as low as possible:observations at a steep angle should be avoided. The darkness of the smoke at the point where it leaves the chimneyshould be compared with the shades of th
29、e chart, the number of theshade which appears most closely to match the darkness of the smokedetermined, and the time of duration of this darkness of smokenoted. The darkness of smoke which is intermediate between twoshades may be estimated to the nearest quarter Ringelmann numberin favourable condi
30、tions.BRITISH STANDARD BSI 2009 3BS 2742:2009The chart will become soiled in use and the observed Ringelmannnumber of the smoke will be less than the true value. It is essential,therefore, that a used chart should be discarded as soon as it becomesappreciably soiled or discoloured.3.2 The BS miniatu
31、re smoke chart, BS 2742M3.2.1 GeneralIn practice, it has been found that there are many situations wherea BS Ringelmann chart cannot conveniently be used. Use of thestandard chart might, in many circumstances, require the services ofan assistant to hold the chart for the observer, for example, where
32、it is not possible to fix the chart on a building to meet the aboverecommendations in 3.1.2. Accordingly, the British Standard mini-ature smoke chart, BS 2742M, has been developed for use withoutassistance in such situations.The miniature chart has been prepared to the same precision as the BS Ringe
33、lmann chart; results obtained are similar (although notidentical) to those from the BS Ringelmann chart and the miniaturechart may conveniently be used for readings of a preliminary nature. The grey shades painted on the miniature chart are arranged to cor-respond with the similar shades printed on
34、the BS Ringelmann chart. 3.2.2 Before use The chart is designed for use at a distance of less than 2 m from theobservers eye. It is to be used under the conditions of illuminationin 3.1.2. 3.2.3 Using the miniature smoke chartPreferably, the chart should be held at a distance of 1.5 m from theobserv
35、ers eye. Figure B.3 shows a suitable holder which can be fixedto the end of a light rod. (A telescopic rod is convenient for carrying.)The chart may also be held at arms length, but observers are likely tofind that it is then less easy to obtain readings agreeing with thoseobtained with the British
36、Standard Ringelmann chart, BS 2742C.NOTE BSI requests all thoseusers who are able to conduct,or have conducted, quantitativecomparisons between theminiature chart and the standardRingelmann chart to send theirresults to the committee via BSI.BS 2742:20094 BSI 2009BRITISH STANDARDAnnex A (informative
37、) Format of Ringelmann chartsThe BS Ringelmann charts are in two formats, standard and miniature.The standard chart BS 2742C is a series of four sections, printed withapproximately 5% luminance ink on approximately 80% luminancecard, to appear identical to Professor Ringelmanns original chartswhen h
38、eld at the recommended distance. There are also two controlareas on the chart. The chart is printed on card to prevent creasingand present an even shade when in the holder. It is supplied trimmedto fit in the holder described in Figure B.1. The rule given by Professor Ringelmann gave the following d
39、imensions:1: Black lines 1.06 mm thick, 10 mm apart, leaving white spaces 8.94 mm square.2: Black lines 2.25 mm thick, spaces 7.75 mm square.3: Black lines 3.68 mm thick, spaces 6.32 mm square.4: Black lines 5.53 mm thick, spaces 4.47 mm square.The paper and ink used by Professor Ringelmann was diff
40、erent fromthat used in BS 2742C, and that BS 2742C uses lines and spaces reducedto a 5 mm square rather than 10 mm square.The miniature chart BS 2742M is a series of five paint swatchesmounted on a card, the colours corresponding to those in BS 5252and selected to appear identical to BS 2742C (when
41、in use). Thecard is supplied with an instructional envelope and with additionalprotection for the paint swatches.Users are reminded that this British Standard is only for use with theBS charts.BRITISH STANDARD BSI 2009 5BS 2742:2009Annex B (informative) Chart holders and use of the chart BS 2742CThi
42、s Annex shows examples of suitable holders for the Ringelmannchart (see Figure B.1) and the miniature smoke chart (see Figure B.3)and an example of the use of the Ringelmann chart (see Figure B.2).Figure B.1 Suitable holder for BS 2742C Ringelmann chartDimensions in millimetresAAThin aluminium sheet
43、 turned over to form frame on one side and both endsScrew holes for attachment of holder to suitable pole or post by means of countersunk headed screws590130161.6Section A-A(enlarged)BS 2742:20096 BSI 2009BRITISH STANDARDFigure B.2 Sketch showing method of use of British Standard Ringelmann chartLin
44、e of sightFigure B.3 Suitable holder for BS 2742M miniature smoke chartDimensions in millimetres7020 25 135Thin aluminiumsheet with flangeturned over as shownSpring clipFlange shapedas shown togrip cardBRITISH STANDARD BSI 2009 7BS 2742:2009BibliographyStandards publicationsFor dated references, onl
45、y the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.BS 5252, Framework for colour co-ordination for building purposesBS 2742:2009 BRITISH STANDARDThis page deliberately left blankThis page deliberately left blankBSI is
46、 the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter.British Standards Institution (BSI)raising standards worldwideBSI Group Headquarters389 Chiswick High Road Lo
47、ndon W4 4AL UKTel +44 (0)20 8996 9001Fax +44 (0)20 8996 Standards are updated by amendment or revision. Users of BritishStandards should make sure that they possess the latest amendments oreditions.It is the constant aim of BSI to improve the quality of our products andservices. We would be gratefu
48、l if anyone finding an inaccuracy orambiguity while using this British Standard would inform the Secretary ofthe technical committee responsible, the identity of which can be foundon the inside front cover.Tel: +44 (0)20 8996 9000 Fax: +44 (0)20 8996 7400BSI offers members an individual updating ser
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