How To Develop A Regulatory Compliant QA/QC Program For Your CMS – Part 1

During a regulatory inspection or audit you may be asked to provide a Quality Assurance/Quality Control (QA/QC) Plan for your Continuous Monitoring System (CMS). You provide the QA/QC Plan, and the inspector/auditor determines that the QA/QC Plan is robust enough or has an ample number of pages and checks the box that the facility has a QA/QC Plan for their CMS. But does simply having a QA/QC Plan satisfy the regulatory requirement? The regulatory requirement for a QA/QC Plan is primarily driven by 40 CFR Part 60, Appendix F, Procedure 1 for Continuous Emissions Monitoring Systems (CEMS) [Appendix F (P1)] and Procedure 3 for Continuous Opacity Monitoring Systems (COMS) [Appendix F (P3)]. Of course, there are similar requirements in applicable General Provisions and/or specific Subparts which we will explore later. But where does a regulatory requirement actually say that a QA/QC Plan is necessary for your CMS? See Appendix F (P1) §3.0 [with similar language in Appendix F (P3) §9.0]:

“Each source owner or operator must develop and implement a QC program. As a minimum, each QC program must include written procedures which should describe in detail, complete, step-by-step procedures and operations for each of the following activities…”

Let’s explore these (and similar) requirements that will be the focus of an upcoming series of ALL4 4 The Record articles on CMS. The series on QC Programs for CMS will include:

1. Terminology – Where is the QA? I am as guilty as the next person who interchangeably uses QA and QC. In fact, saying QC just feels wrong because I have been misusing the terms for so long. So, I guess it is time that we all change the way we use QA and QC. The proper use of the terms QA and QC is further discussed in this article.
2. Requirements – Where is the requirement for a QA/QC Plan? What is the requirement for a QA/QC Plan? There is a clear connection between written procedures and plans, but the more important requirement is in the terminology of develop, implement, and program. Does just having a QA/QC Plan for your CEMS make it a program that is implemented? How do we assess compliance with terms like implemented? That sounds like a great topic for an upcoming article on QC Programs.
3. Nuances – There may not be much ambiguity about written, but what about detail, complete, step-by-step? Developing detail[ed], complete, step-by-step procedures (based on your interpretation) can take a lot of effort and iterations. Should the procedures be detailed and complete enough so I can give them to someone off the street to complete the QC activities for my CMS? Another great topic for an upcoming article on QC Programs for CMS.
4. Miscellaneous – With anything, there are a lot of caveats and other things to consider. Wrapping up those items warrants an article as well!

But for this first 4 The Record article on QC Programs for CMS, let’s explore the terminology QA and QC.

What is QA/QC?

The terms QA and QC are often used interchangeably, but let’s explore the difference. QC, which stands for Quality Control, can be defined as activities performed to provide a reproducible quality product. It addresses how the facility will handle issues that arise with the CMS. One example of a QC activity is corrective maintenance. Corrective maintenance should be performed if an issue arises with the CMS [e.g., a cylinder gas audit (CGA) fails, a daily validation exceeds the allowable drift limit, etc.]. It is performed to ensure data quality is not compromised following an issue with the CMS. After the corrective maintenance is completed, additional QC activities such as an analyzer calibration and/or calibration drift test need to be completed. In addition, QC activities are typically performed by a person who works at the facility and include activities during the CMS procurement, certification, and ongoing operation. QC activities are sometimes referred to as internal quality control.

QA, which stands for Quality Assurance, can be defined as activities implemented to ensure quality control activities are being performed adequately. QA addresses how the facility can be confident that the data produced by the CMS is accurate and reliable. One example of a QA activity is a CGA for CEMS. Once every quarter, an audit gas containing a pollutant of known concentration is injected into the system at two different audit points three times each and read by the analyzer to assess if the analyzer is providing accurate readings. If the readings are within the specification, the analyzer is correctly measuring concentrations of that particular pollutant. This is an example of quality assurance because the activity is performed for the purpose of confirming the reliability of the data. In addition, it may be performed by a third party (not a regulatory requirement) – someone outside of the normal routine operations. This is another indication of a QA activity, which is sometimes referred to as external quality control.

QA and QC activities are both required to be implemented as part of a facility’s QA/QC Program (or QC Program). To support the program as opposed to the document, there must be written, detailed, step-by-step procedures and operations for the various required QA and QC activities at the facility. Many times this procedure is referred to as a QA/QC Plan or a Quality Assurance Plan (QAP). This document is part of the program that attempts to answer the two questions, “How can quality of data be assured?” (QA) and “What actions will be taken (implemented, revised, modified) to address issues with QA activities?” (QC).

Conclusion

In conclusion, QA/QC programs define QC activities (internal, first-step) and QA activities (internal or external, second-step, oversight) that frame oversight for collection of usable, understandable, meaningful data. As part of a QA/QC program, QA/QC Plans codify activities and responses necessary to maintain CMS data quality at acceptable levels. However, they are only part of the overall QA/QC program required at facilities with a CMS. The second part of this series will address the specific elements required in a QA/QC Program to execute a QC Program that is fully developed, implemented, and executed. ALL4’s CMS-focused team is committed to publishing several follow-up blogs for QA/QC Programs for CMS throughout 2025. If you have any CMS-related questions, need help assessing or updating a CMS QA/QC Program, or want to suggest additional topics please email Eric Swisher (eswisher@all4inc.com) or Corey Weiss (cweiss@all4inc.com).