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  2. Air Emission Measurement Center (EMC)

Method 9 - Visual Opacity

Do you have questions about a Test Method, Performance Specification or Source Category? Find the EMC contact for your question in the EMC Directory.

Supporting Information

  • Visible Emissions Field Manual (PDF) (48 pp, 4 MB)
  • Visible Emissions Evaluation Procedures Course (PDF) (176 pp, 9 MB)
  • Collaborative Study (PDF)
  • Optical Properties and Visual Effects of Smoke Stack Plumes (PDF)
  • Section 3.12 of the QA Handbook, Volume III (PDF) (63 pp, 6 MB)
  • Visible Emissions Certification Program Evaluation Form (PDF) (17 pp, 30 K)
  • Self-Audit Guide for Visible Emissions Certification Programs (PDF) (34 pp, 2 MB)
  • Quality Assurance Guideline for Visible Emissions Training (PDF)
  • Smoke Generator Troubleshooting (PDF) (23 pp, 230 K)
  • Guidelines for Evaluation of Visible Emissions (PDF)
  • Guidelines for Quality Assurance Program for Visible Emissions (PDF)
  • Visible Emissions Program Operations Manual (PDF)
  • Instructions for Visible Emissions Observation Form (PDF) (22 pp, 1 MB)

Method and FAQ

  • Method 9 Visual determination of the opacity of emissions from stationary sources 8-3-2017 (PDF) (8 pp, 436 K)
    CFR Promulgated Test Method 9 Visual determination of the opacity of emissions from stationary sources.
  • Frequently Asked Questions (FAQs) for Method 9 (PDF) (1 pg, 146 K)

Air Emission Measurement Center (EMC)

  • Test Methods
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  • Recent Additions
Contact Us About Air Emission Measurements
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on August 11, 2024
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