EPA Method 9 Visual Determination Of The Opacity Of Emissions From Stationary Sources
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ID： |
622590B80666413382A577A798F7009B |
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文件大小(MB)： |
0.17 |
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页数： |
8 |
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文件格式： |
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日期： |
2011-5-20 |
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文本摘录（文本识别可能有误，但文件阅览显示及打印正常，pdf文件可进行文字搜索定位）：
311,Environmental Protection Agency Pt. 60, App. A–4, Meth. 9,METHOD 9—VISUAL DETERMINATION OF THE,OPACITY OF EMISSIONS FROM STATIONARY,SOURCES,Many stationary sources discharge visible,emissions into the atmosphere; these emissions,are usually in the shape of a plume.,This method involves the determination of,plume opacity by qualified observers. The,method includes procedures for the training,and certification of observers, and procedures,to be used in the field for determination,of plume opacity. The appearance of a,plume as viewed by an observer depends upon,a number of variables, some of which may be,controllable and some of which may not be,controllable in the field. Variables which can,be controlled to an extent to which they no,longer exert a significant influence upon,VerDate Nov<24>2008 14:47 Aug 31, 2009 Jkt 217149 PO 00000 Frm 00321 Fmt 8010 Sfmt 8002 Y:\SGML\217149.XXX 217149,ER17OC00.226,cprice-sewell on DSK2BSOYB1PROD with CFR,312,Pt. 60, App. A–4, Meth. 9 40 CFR Ch. I (7–1–09 Edition),1 For a set, positive error=average opacity,determined by observers’ 25 observations—,average opacity determined from,transmissometer’s 25 recordings.,plume appearance include: Angle of the observer,with respect to the plume; angle of,the observer with respect to the sun; point of,observation of attached and detached steam,plume; and angle of the observer with respect,to a plume emitted from a rectangular,stack with a large length to width ratio. The,method includes specific criteria applicable,to these variables.,Other variables which may not be controllable,in the field are luminescence and color,contrast between the plume and the background,against which the plume is viewed.,These variables exert an influence upon the,appearance of a plume as viewed by an observer,and can affect the ability of the observer,to accurately assign opacity values to,the observed plume. Studies of the theory of,plume opacity and field studies have demonstrated,that a plume is most visible and,presents the greatest apparent opacity when,viewed against a contrasting background. It,follows from this, and is confirmed by field,trials, that the opacity of a plume, viewed,under conditions where a contrasting background,is present can be assigned with the,greatest degree of accuracy. However, the,potential for a positive error is also the,greatest when a plume is viewed under such,contrasting conditions. Under conditions,presenting a less contrasting background,the apparent opacity of a plume is less and,approaches zero as the color and luminescence,contrast decrease toward zero. As a result,significant negative bias and negative,errors can be made when a plume is viewed,under less contrasting conditions. A negative,bias decreases rather than increases the possibility,that a plant operator will be cited,for a violation of opacity standards due to,observer error.,Studies have been undertaken to determine,the magnitude of positive errors which,can be made by qualified observers while,reading plumes under contrasting conditions,and using the procedures set forth in this,method. The results of these studies (field,trials) which involve a total of 769 sets of 25,readings each are as follows:,(1) For black plumes (133 sets at a smoke,generator), 100 percent of the sets were read,with a positive error 1 of less than 7.5 percent,opacity; 99 percent were read with a positive,error of less than 5 percent opacity.,(2) For white plumes (170 sets at a smoke,generator, 168 sets at a coal-fired power,plant, 298 sets at a sulfuric acid plant), 99,percent of the sets were read with a positive,error of less than 7.5 percent opacity; 95 percent,were read with a positive error of less,than 5 percent opacity.,The positive observational error associated,with an average of twenty-five readings is,therefore established. The accuracy of the,method must be taken into account when determining,possible violations of applicable,opacity standards.,1. Principle and Applicability,1.1 Principle. The opacity of emissions,from stationary sources is determined visually,by a qualified observer.,1.2 Applicability. This method is applicable,for the determination of the opacity of emissions,from stationary sources pursuant to,§ 60.11(b) and for qualifying observers for visually,determining opacity of emissions.,2. Procedures,The observer qualified in accordance with,section 3 of this method shall use the following,procedures for visually determining,the opacity of emissions:,2.1 Position. The qualified observer shall,stand at a distance sufficient to provide a,clear view of the emissions with the sun oriented,in the 140° sector to his ba……
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