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Air Emission Measurement Center (EMC)

Method 203A - Opacity Determination for Time-Averaged Regulations

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Method 203A Visual Determination of Opacity of Emissions from Stationary Sources for Time-Averaged Regulations 8-4-2017 (PDF)(8 pp, 400 K)
Promulgated CFR Test Method 203A Visual Determination of Opacity of Emissions from Stationary Sources for Time-Averaged Regulations.
Frequently Asked Questions (FAQs) for Method 203A (PDF)(1 pg, 176 K, August 2016)