1、Designation: D7520 09Standard Test Method forDetermining the Opacity of a Plume in the Outdoor AmbientAtmosphere1This standard is issued under the fixed designation D7520; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes the procedures to determinethe opacity of a plume. The aforementioned plume is caused bypa
3、rticulate matter emitted from a stationary point source in theoutdoor ambient environment using digital imagery and asso-ciated software and hardware.1.2 The opacity of emissions is determined by the applica-tion of a Digital Camera Opacity Technique (DCOT) thatconsists of a Digital Still Camera, An
4、alysis Software, and theOutput Functions content to obtain and interpret digital imagesto determine and report plume opacity.1.3 This method is suitable to determine the opacity ofplumes from zero (0) percent to one hundred (100) percent.1.4 This test method is not applicable to stacks with internal
5、diameters greater than 7.0 ft.21.5 Conditions that shall be considered when using thismethod to obtain the digital image of the plume include theplumes background, the existence of condensed water in theplume, orientation of the Digital Still Camera to the plume andthe sun (see Section 8).1.6 This s
6、tandard describes the procedures to certify theDCOT, hardware, software, and method to determine theopacity of the plumes.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-
7、priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D1356 Terminology Relating to Sampling and Analysis ofAtmospheresE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a
8、Test Method2.2 U.S. Environmental Protection Agency (USEPA) Docu-ment:4USEPA Method 9 Visual Determination of the Opacity ofEmissions from Stationary Sources, 40 CFR, Part 60,Appendix A-42.3 Institute of Electrical and Electronics Engineers (IEEE)Document:5IEEE 12207-2008 Systems and Software Engine
9、eringSoftware Life Cycle Processes (ISO/IEC 12207:2008(E),Edition: 2nd, Institute of Electrical and Electronics Engi-neers, 01-Feb-2008, 138 pages, ISBN: 97807381566372.4 Japanese Electronic and Information Technology In-dustries Association (JEITA) Document:Exchangeable Image File Format (EXIF) for
10、 Digital StillCameras: Joint Photographic Experts Group: JPEG fileformat version 2.21, JEITA CP-3451-1 (English version)dated 2003-09; http:/www.jeita.or.jp/english/standard/list/list.asp?cateid=1 b) producesopacity measurements from the combination of human inter-action, open or proprietary calcula
11、tions and algorithms, and1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emissions.Current edition approved Nov. 1, 2009. Published January 2010.2The 7.0 ft limitation was set as
12、a reasonable boundary for the initial issuing ofthis test method due to there being a limited amount of data for large diameterstacks.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume info
13、rmation, refer to the standards Document Summary page onthe ASTM website.4Available from United State Environmental Protection Agency (USEPA), ArielRios Bldg, 1200 Pennsylvania Ave., NW, Washington, DC 20460, http:/www.epa.org.5Available from Institute of Electrical and Electronics Engineers, Inc.,
14、(IEEE),1828 L St., NW, Suite 1202, Washington, DC 20036-5104, http:/www.ieee.org.6Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 194
15、28-2959, United States.image content viewing; c) and then output said opacitymeasurement along with Analysis Softwares configuration,image source documentation and other environmental param-eters.3.2.2 certifiedfor the purpose of this standard, certifiedrefers to achieving or excelling the requireme
16、nts described inthis method.3.2.3 DCOT operatorrefers to the human operating theDCOT system who records the digital still images with theDigital Still Camera and then determines plume opacity withthe Analysis Software.3.2.4 Digital Still Cameraan image capture device usedto collect store and forward
17、 digital still images to the AnalysisSoftware for analysis as defined by the DCOT vendorscertification documentation.3.2.5 image transfer filean electronic file that contains theimage captured by the Digital Still Camera and its associatedenvironment documentation that is consistent with EXIF 2.1JPG
18、 (or higher) format and is input to the Analysis Software.All of the digital images obtained by a DCOT system shall bereviewed by a qualified human DCOT operator to assess if thedigital images are acceptable (for example, no obvious errorsin the digital images).3.2.6 opacitymeasurement of the degree
19、 to which particu-late emissions reduce the intensity of transmitted photopic lightand obscure the view of an object through an effluent gasstream of a given path length in ambient air.3.2.7 opacity sourceany source that produces emissionsthat are visible to the human eye.3.2.8 output functionhuman
20、readable information docu-menting the image being analyzed and configuration of theAnalysis Software used, the opacity measurement and the otherrequired environment variables defined (for example, viewangle, wind direction).4. Summary of Test Method4.1 A Digital Still Camera is used to capture a set
21、 of digitalimages of a plume against a contrasting background. Eachimage is analyzed with software that determines plume opacityby comparing a user defined portion of the plume image whereopacity is being measured in comparison to the backgroundproviding the contrasting values. The Analysis Software
22、 isused to average the opacities from the series of digital imagestaken of the plume over a fixed period of time. The software isalso used to archive the image set utilized for each opacitydetermination including the portion of each image selected bythe operator.4.2 The following conditions must be
23、followed to make avalid opacity determination:4.2.1 The image must be captured in a JPEG format thatadheres to the EXIF 2.1 (or higher) standard.4.2.2 The image must be captured with the sun locatedbehind the Digital Still Camera and within a 140 sectordirectly behind the Digital Still Camera (see T
24、able 1 forschematic).4.2.3 The image must be captured perpendicular to thedirection of plume travel.4.2.4 Digital enhancement capabilities of the Digital StillCamera (that is, flash, optical filters, digital zoom, and imagestabilization) shall not be used. However, the Digital StillCameras optical z
25、oom may be used when capturing the digitalstill image.4.2.5 The ambient light must be sufficient to show a clearcontrast between the plume and its background.4.2.6 The portion of the plume selected for opacity deter-mination shall not contain condensed water vapor.4.2.7 The selected portions of each
26、 image representing thevisible plume and the uniform background must contrastsufficiently for the software to differentiate between the plumeand its background.4.2.8 The portion of the plume selected for opacity deter-mination shall represent the part of the plume with the highestapparent opacity, e
27、xcluding water vapor, as determined by theDCOT operator.4.2.9 The area of the digital image to be analyzed foropacity shall be centered in the digital image when taking thephotograph.4.2.10 Each DCOT vendor shall provide training for opera-tors of their DCOT system. The training shall include thecon
28、tent of the “Principles of Visual Emissions Measurementsand Procedures to Evaluate those Emissions Using the DigitalCamera Optical Technique (DCOT)” (Annex A1) and a de-scription of how to operate that specific DCOT system thatpassed smoke school.5. Significance and Use5.1 Air permits from regulator
29、y agencies often requiremeasurements of opacity from stationary air pollution pointsources in the outdoor ambient environment. Opacity has beenvisually measured by certified smoke readers in accordancewith USEPA (USEPA Method 9). DCOT is also a method todetermine plume opacity in the outdoor ambient
30、 environment.5.2 The concept of DCOT was based on previous methoddevelopment using Digital Still Cameras and field testing ofthose methods.7,8The purpose of this standard is to set aminimum level of performance for products that use DCOT todetermine plume opacity in ambient environments.6. Interfere
31、nces6.1 ContrastAs the contrast between the color of theplume and the background decreases, the observed opacitydecreases. To achieve maximum opacity, the opacity shall bemeasured at a point where the maximum contrast existsbetween the plume and the background.6.2 LuminescenceLow light levels advers
32、ely impact thedetermination of plume opacity.Adequate natural light must beavailable to illuminate the plume and background during theperiod the images are captured. This method shall only be usedduring daytime conditions.7Du, K., Rood, M. J., Kim, B. J., Kemme, M. R., Franek, B. J., and Mattison,K.
33、, Quantification of Plume Opacity by Digital Photography, Environmental Sciencedigital image; digital still camera;opacityANNEXESA1. PRINCIPLES OF VISUAL EMISSIONS MEASUREMENTS AND PROCEDURES TO EVALUATE THOSE EMISSIONSUSING DIGITAL CAMERA OPTICAL TECHNIQUE (DCOT)A1.1 AbstractA1.1.1 This document wa
34、s developed to provide back-ground information pertaining to the principles of visualemission measurement, United States Environmental Protec-tion Agency (USEPA) Reference Method 9 requirements,ASTM Standard Practice for Competence of Air EmissionTesting Bodies, equipment needed to collect visual em
35、issiondata for the Digital Camera Optical Technique (DCOT),documentation needed when measuring visual emissions withDCOT, and the certification and duration of certification ofDCOT. DCOT was developed as a possible alternative toMethod 9 and this document provides background informationabout Method
36、9 that is also applicable to DCOT.A1.1.2 A note about terminology: the term “observer” isused in this document when referring to Method 9 to describethe person who is making a visual emission evaluation todetermine plume opacity. However, “observer” is replacedwith “Digital Still Camera” when referr
37、ing to DCOT as themeans to record digital still images that are then used todetermine plume opacity. The term “operator” is used whenreferring to DCOT to describe the operation of the Digital StillCamera that obtains the digital still images and the collectionof supporting documentation that are nee
38、ded to provide acomplete dataset for DCOT to determine plume opacity.A1.1.3 An extensive amount of the information providedbelow is from the student manual for the “Visible EmissionEvaluation Procedures Course,” Air Pollution Training Insti-tute (APTI) Course 325, Final Review Draft (January 1995).T
39、he principal author of the student manual is Thomas H. Rosewith style and editing by Monica L. Loewy.A1.2 Table of ContentsAbstract A1.1Table of Contents A1.2List of Figures A1.3Principles of Visual Emissions Measurement A1.4Ringelmann Method A1.4.1Equivalent Opacity A1.4.2Opacity and Transmission o
40、f Light A1.4.3Light and Particles A1.4.4Absorption A1.4.5Scattered Light A1.4.6Rayleigh Scattering A1.4.7Mie Scattering A1.4.8Particle Size A1.4.9Variables Influencing Opacity Observations A1.4.10Selecting the Background A1.4.11Method 9 Requirements A1.5Method 9 A1.5.1The Reference Method is one of
41、Observation A1.5.2Opacity Variances A1.5.3Changes in USEPA Procedures A1.5.4Analysis of Error A1.5.5Averaging was Introduced to Increase Accuracy A1.5.6Sun Position became an Issue A1.5.7Slant-Angle Considerations were Introduced A1.5.8The Issue of Steam Source Plumes was Introduced A1.5.9Smoke Gene
42、rators were Standardized A1.5.10Minor Changes to the Method A1.5.11Appearance and Controllable Observational Variables A1.5.12Appearance and Uncontrollable Observational Variables A1.5.13High-Contrast Backgrounds A1.5.14Low-Contrast Backgrounds A1.5.15Positive Error Defined A1.5.16Positive Observati
43、onal Error A1.5.17D7520 097Principle A1.5.18Applicability A1.5.19Procedures A1.5.20Observer Position Relative to the Sun Notes A1.5.21Observer Line of Sight A1.5.22Multiple Stacks A1.5.23Field Records A1.5.24Observation Point in the Plume A1.5.25Attached Steam Plumes A1.5.26Detached Steam Plumes A1.
44、5.27Recording Observations A1.5.28Data Reduction A1.5.29Calculation of Opacity A1.5.30General Certification Requirements A1.5.31Period of Certification A1.5.32Introduction to Digital Camera Opacity Technique (DCOT) A1.6Equipment to Determine Plume Opacity in the Field UsingDigital Camera Opacity Tec
45、hniqueA1.7Introduction A1.7.1Digital Camera Opacity Technique (DCOT) A1.7.2Tripod A1.7.3Timer/Watch A1.7.4Direction Finder A1.7.5Rangefinder A1.7.6Clinometric Devices A1.7.7Anemometer A1.7.8Relative Humidity Sensor A1.7.9Documentation Needed to Determine Plume Opacitywith DCOTA1.8Company Name and Lo
46、cation A1.8.1Test Identification Number and Date A1.8.2Type and Operational Status of the Facility, ProcessUnit and Control DeviceA1.8.3Height of Emission Point and Estimation Method A1.8.4Description of Operator, DCOT and Digital Still Camera A1.8.5Source Layout Sketch A1.8.6Clock Time A1.8.7Camera
47、s Location A1.8.8Environmental Conditions A1.8.9Plume Description A1.8.10Additional Information A1.8.11Operators Signature and Date A1.8.12Certification of DCOT A1.9Testing Requirements A1.9.1Grading A1.9.2Certification of DCOT and Certification Period A1.9.3Knowledgeable Users A1.10Testing Requirem
48、ents A1.10.1Grading A1.10.2Certification of Digital Still Camera Operators A1.10.3A1.3 List of FiguresRingelmann Chart Fig. A1.1Electromagnetic Spectrum Fig. A1.2Dependence of Slant Angle on Distance between the Observerand PlumeFig. A1.3Orientation of the Observer to the Plume and Sun Fig. A1.4Effe
49、ct of Slant Angle on Path Length and Apparent Opacity Fig. A1.5Card-Type and Needle-Type Compasses Fig. A1.6Sling Psychrometer Fig. A1.7Slant-Angle Determination Fig. A1.8A1.4 Principles of Visual Emissions MeasurementThissection describes concepts related to opacity and discusses thescientific principles associated with measuring opacity and thepractical application of those principles.A1.4.1 Ringelmann Method:A1.4.1.1 Evaluation of visible emissions evolved from aconcept developed by Maximillian Ringelmann during the late1800s. Ringelmann used a chart of cali
