How To Develop A Regulatory Compliant QA/QC Program For Your CMS – Part 2

In Part 1 of this 4 The Record article series, the terminology for Quality Assurance (QA) and Quality Control (QC) was defined and discussed. QA activities, such as cylinder gas audits (CGAs) and relative accuracy test audits (RATAs), ensure quality control activities are adequately performed. QC activities, which include activities such as daily calibration drift (CD) tests and maintenance, ensure a reproducible quality product. QC activities are inherently part of a facility’s QA, as QC activities are performed to ensure data continues to accurately represent emissions at the facility. The implementation of a QC Program is one of the ways a facility complies with QA requirements.

Regulatory Requirements

Various air quality regulations require use of continuous monitoring systems (CMS) to demonstrate or indicate compliance with applicable emissions standards and/or operating limits. The most common examples include 40 CFR Part 60, Part 63, and Part 75; these regulations also contain QA and QC requirements for CMS. This 4 The Record article, Part 2 of the series, focuses on the requirements of a CMS QC Program (also referred to as “QA/QC Program” in 40 CFR Part 75 and “Site Specific Monitoring Plan” in 40 CFR Part 63). As an example, 40 CFR Part 60, Appendix F is titled “Quality Assurance Procedures,” and each procedure in Appendix F outlines quality assurance requirements for different types of monitoring systems [e.g., Appendix F, Procedure 1 (P1) is titled, “Quality Assurance Requirements for Gas Continuous Emission Monitoring Systems Used for Compliance Determination”]. P1 requires the development and implementation of a QC Program. Note that there is no direct requirement in P1 for a CMS QA/QC Plan. However, P1 requires written procedures that describe in detail, complete, step-by-step procedures and operations for certain QA and QC activities. Those procedures (in addition to other items identified in QA/QC programs) are the basis for our QA/QC Plan.

Having a QA/QC Plan alone does not satisfy the requirement. The requirement is to “develop and implement a QC program.” The QA/QC Plan serves to satisfy the “written procedures” part of the requirement. To fully satisfy the requirement of a “QC program” the specified QA and QC activities must be developed and implemented.

QC Program Success

Let’s explore what success looks like when developing and implementing a QC program; at the end of the day that is the regulatory requirement. To do that, we ask ourselves what the measurement objectives of the program are, and what the QA objectives are. In this case, we are tasked with evaluating the quality of data collected by monitoring systems used in determining compliance with emissions standards on a continuous basis. At the same time, we are tasked with minimizing the time during which the monitoring systems are malfunctioning (not producing representative data) or out-of-control (as defined by the applicable regulations). The measure of success for a QC program could be overall amount of acceptable data, or it could be the amount of compliant results. Minimal downtime equals a successful QC program, right? Or maybe you’ve been lucky, and your QC program has not yet been challenged with recurring corrective maintenance activities, frequent excess calibration drifts, etc. To assess your CMS QC program, review the CMS downtime for the last year. Regardless of the amount of CMS downtime reported, look at the individual events. Was the downtime a result of the same root cause? Was the root cause even determined? What actions were taken to minimize the CMS downtime events from recurring? What interaction was there between environmental personnel and instrumentation technicians for the CMS downtime events? If your CMS downtime reporting feels like an exercise completed with the only goal to submit the CMS downtime report on time, then it is time to reassess your CMS QC program. If you’re still wondering about the effectiveness of your QA/QC program, ask when was the last time your environmental, operations, and instrumentation personnel were trained on the data quality objectives for CMS.

The following paragraphs discuss examples of QA and QC activities required by P1. Note that the QA and QC activities as part of 40 CFR Part 60, Appendix F, Procedure 3 (P3) and Part 75 have similar requirements to meet the data quality objectives of those rules.

Calibration Procedures

A QA/QC Program is required to contain and implement procedures for calibrations. Section 4 of P1 describes the requirements for CD Assessments. Owners and operators of sources monitored by CMS must quantify CD at two different concentration values (known as the zero or low-level calibration and the high-level calibration) at approximately every 24 hours. During a CD Test, a reference gas containing a known pollutant is introduced to the system, passes through the system, is read by the analyzer, and is compared to the known concentration of the pollutant using the CD equation specified in Appendix B. If the drift on either level exceeds two times the applicable drift specification for five consecutive days, or the drift on either level exceeds four times the applicable drift specification at any time, the CMS is out of control, and corrective action must be taken.

Even if you have the written procedures for the CD task itself, does your QC program provide structure for implementing procedures, include preventative measures to predict CMS failures, or describe the process for corrective actions (especially on weekends and holidays)? If not, then your CMS could be at risk for excessive downtime due to CMS malfunctions that are not repaired promptly.

Preventive and Corrective Maintenance

Procedures for preventive and corrective maintenance are required to be maintained within the QA/QC Plan and implemented when necessary. Preventive maintenance is maintenance performed on the CMS on a regular basis with the intention of minimizing CMS malfunctions. It should be performed in accordance with standard industry practices and the manufacturer’s recommendations. Preventive maintenance should be tracked and recorded as part of the QA/QC Program, and a list of spare parts should be documented in the QA/QC Plan, or somewhere else on-site (and, of course, stocked on-site). Corrective maintenance is maintenance that occurs as a result of a CMS malfunction. It is performed as a reaction to a CMS malfunction, whereas preventive maintenance is a proactive measure. Similar to preventive maintenance, corrective maintenance should be performed in accordance with standard industry practices and the manufacturer’s recommendations. It should be tracked and recorded as part of the QA/QC Program. In addition, common maintenance activities and their procedures, as well as follow-up quality assurance activities, should be recorded in the QA/QC Plan.

If the CMS breaks, you fix it. When was the last time your CMS (from probe tip to data acquisition) was evaluated for remaining expected life? Are spare parts available for your CMS? Is the vendor still supporting your CMS make and model? Obsolescence planning for CMS is an important part of a good QC Program. Replace your CMS on your terms, not in response to a catastrophic failure.

Data Recording, Calculations, and Reporting

Procedures for recording, calculating, and reporting data must be documented in the QA/QC Plan and implemented. Data is often recorded in a data acquisition and handling system (DAHS). The DAHS can also calculate a result in terms of the emissions standard from measured data. Although a DAHS is not required by name in 40 CFR Part 60 Appendix B or Appendix F, or 40 CFR Part 75, it is a helpful tool for implementing data recording, calculations, and generating reports. However, at a minimum, data calculations, applicable averaging periods, and reporting procedures must be described in your QA/QC Plan and be properly implemented.

What magic does your “black box” do? Knowing how your data is managed is a regulatory requirement and manages risk. From measurement, your data’s journey can involve many different elements (PLCs, data loggers, DCS, PI, DAHS, etc.). Understanding what each element does to your data is equally important to how the calculations are performed.

Accuracy Audit Procedures

Procedures for quarterly and annual audits are required to be documented and implemented. For gas continuous emissions monitoring systems (CEMS) subject to 40 CFR Part 60 Appendix F, quarterly audits are called CGAs and are specified in P1. During a CGA, an analyzer is challenged three times with an audit gas of known concentrations at two points within the concentration ranges. The average of the three responses for each audit point is used to determine accuracy. If the accuracy does not meet the passing criteria specified in P1, the CGA fails, corrective maintenance must be performed, and an audit must be performed again. The annual audit, called a RATA by P1, is required to be conducted at least once every four calendar quarters, and as part of initial certification procedures. A RATA is a comparison of the CEMS results to a reference method. They must be performed in accordance with the reference method in Appendix A to 40 CFR Part 60 corresponding to the pollutant being tested. If the accuracy does not meet the passing criteria specified in the applicable performance specification in Appendix B, the RATA fails, corrective maintenance must be performed, and the RATA must be performed again.

Conclusion

When developing or evaluating a QC Program at your facility, it is important to remember the following:

• A QC Program cannot be implemented without QA and QC activities.
• A QA/QC Plan alone is not sufficient to meet the requirement to “develop and implement a QC program.” The implementation and completion of the activities outlined in the QA/QC Plan must also occur.
• Minimal downtime does not always indicate a successful QC Program. It is important to identify the root cause of downtime, take action to minimize future downtime, and train facility personnel on data quality objectives for CMS.

Part 3 of this series will address the nuances in the development of a QC Program. For example, what is meant by “detail”, “complete”, or “step-by-step”? 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).