Resources

Resources

Technical references and information to support your opacity monitoring, filter testing, and equipment needs.

Technical References

Regulatory and Standards References

EPA Performance Specification 1 — Opacity

Specifications and test procedures for continuous opacity monitoring systems at stationary sources, along with supporting EPA guidance.

EPA Quality Assurance Procedures

Includes Procedure 3, covering quality assurance requirements for continuous opacity monitoring systems at stationary sources.

EPA Method 9 — Visual Opacity

Information on visually determining the opacity of emissions from stationary sources, including field manuals and training references.

Opacity monitor test filters on a laboratory workbench with precision optical equipment
Opacity monitor sensor mounted on an industrial stack at a processing facility
Industrial facility with smokestacks against a clear blue sky

Filter Testing and Certification

Cal Check provides NIST-traceable filter testing and certification services. For questions about testing your existing filters, replacement filters, or equipment compatibility, contact us to discuss your requirements.

When contacting us, please include your monitor manufacturer and model, filter identification, and any service deadlines.

Training and Technical Support

For assistance with opacity audits, equipment use, data review, or troubleshooting, contact Cal Check to discuss your needs and available training options.

Sending Equipment for Service

Please contact us before shipping to confirm service requirements and scheduling. Include your company name, contact information, equipment identification, and a description of the requested service.

Ship To

Cal Check, Attn: Kieth Boyd, 177 Wembury Lane, Troutman, NC 28166

CalCheck

NIST-traceable opacity monitor test filter certification and replacement filters for industrial emissions compliance.

Serving customers across all 50 states.

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Opacity Monitor Test Filter Certification