Air permits from regulatory agencies often require measurements of opacity from stationary air pollution point sources in the outdoor ambient environment. Opacity has been visually measured by certified smoke readers in accordance with USEPA (USEPA Method 9). DCOT is also a method to determine plume opacity in the outdoor ambient environment.

The concept of DCOT was based on previous method development using Digital Still Cameras and field testing of those methods. ^, The purpose of this standard is to set a minimum level of performance for products that use DCOT to determine plume opacity in ambient environments.

1. Scope

1.1 This test method describes the procedures to determine the opacity of a plume. The aforementioned plume is caused by particulate matter emitted from a stationary point source in the outdoor ambient environment using digital imagery and associated software and hardware.

1.2 The opacity of emissions is determined by the application of a Digital Camera Opacity Technique (DCOT) that consists of a Digital Still Camera, Analysis Software, and the Output Function’s content to obtain and interpret digital images to determine and report plume opacity.

1.3 This method is suitable to determine the opacity of plumes from zero (0) percent to one hundred (100) percent.

1.4 This test method is not applicable to stacks with internal diameters greater than 7.0 ft.

1.5 Conditions that shall be considered when using this method to obtain the digital image of the plume include the plume’s background, the existence of condensed water in the plume, orientation of the Digital Still Camera to the plume and the sun (see Section 8).

1.6 This standard describes the procedures to certify the DCOT, hardware, software, and method to determine the opacity of the plumes.

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D1356 Terminology Relating to Sampling and Analysis of Atmospheres

E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

U.S. Environmental Protection Agency (USEPA) Document

Institute of Electrical and Electronics Engineers (IEEE) Document

Japanese Electronic and Information Technology Industries Association (JEITA) Document

International Organization for Standardization (ISO) Standard

Keywords

digital camera; digital image; digital still camera; opacity;

ICS Code

ICS Number Code 13.040.20 (Ambient atmospheres)

Citing ASTM Standards

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