VEO Form Instructions

Instructions	Forms (PDFs)
Company Identification Emission Description Emission Point Identification Process and Control Equipment	VEO Form - 30 minute VEO Form - 60 minute EPA VEO Form

Emission Point Identification:

Reference Instructions: QA/QC Procedure

Contains Information uniquely identifying the emission point and its spatial relationship with the observer's position. It is recommended that distances and heights in this section be noted in consistent units.

Photographs are useful references in this section providing secondary evidence about the source of emission being investigated and allowing verification with those knowledgeable of the process. Photographs are useful as secondary evidence to show the source, and context of the readings.

Describe the Emission Point:

Describe the type and physical characteristics of the emission point. The descriptions should be specific enough so that the emission outlet can be distinguished from all others at the source (facility). The description of the type of emission point should address whether it is (1) a specifically designed outlet such as a stack, vent or roof monitor (having confined emissions) or (2) an emission source having unconfined emissions such as a storage pile, chemical tank, non-ducted material handling operations. Description of the physical characteristics of the emission point should include the appearance (such as color, texture, etc) and geometry (size, shape, etc) of the stack or outlet, and it's location (if applicable) in relation to other recognizable facility landmarks.

Any special identification codes the agency or source uses to identify a particular stack ( #3 boiler, round Red Brick stack, 70 feet high and 10 feet in diameter) or outlet should be noted along with a description; the source of the code should also be noted (side of stack, facility designation, agency). Don't use the same code used in section A where the Source ID number is provided. Careful examination of this document will show how all the information provided can be used to self-verify the form. Therefore it is important that this section contain information which could be separately referenced to confirm the stack/source has been correctly identified. A special identification code should not be used alone (#3 boiler) to describe the emission point, since they are at times incorrect and also require a secondary reference. The observer must be certain of the source of the emissions being read (the observer must have a clear and unobstructed view). A description of the emission point coupled with the identification of the process equipment and control equipment should accomplish that purpose. If including the height be consistent with the height above ground level. Information should be consistent with and verifiable by the applicable permit information.

Height Above Ground Level:

Indicate the height of the stack or other emission outlet from it's foundation base. This information is usually available from agency files, engineering drawings, or computers printouts (such as the NEDS printouts). The information may be obtained using a combination of a rangefinder and an Abney Level or inclinometer. The height may also be estimated. However be careful not to carry your estimation errors - such as I am 3 stack heights away and the rangefinder gives me 300 feet therefore it is 100 feet.

Height Relative to Observer:

Indicate an estimate of the height of the stack outlet (or other type of emission outlet) above the position of the observer. This measurement indicates the observer's position in relation to the stack base (i.e. higher or lower than the base) and is necessary if slant angle calculations are performed. It is expected to confirm that slant angle calculations are not necessary.

Distance from the Observer:

Record the distance from the point of observation to the emission outlet. This measurement may be made using a rangefinder. A map (or GPS) may also be used to estimate the distance. This measurement must be reasonably accurate when the observer is close to the stack (within three stack heights). Accuracy is important because this may be used in conjunction with the outlet height relative to the observer to determine the slant angle at which the observations were made (see Fig 2). A precise determination of the slant angle becomes important in calculating the precise bias inherent in opacity readings made when the observer is within three stack heights of the stack. Small sources which are accessible may be measured using a measuring tape, roller/counter or paced off by the observer.

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