To understand what this change means, SNIPS News spoke with NADCA Scientific Committee Co-Chairs: Michael J. McDavid, 1st vice president of NADCA and general manager at Professional Abatement & Remediation Technologies in Missouri, and Tyler Batchelder, NADCA treasurer and project manager at Chuck's Heating and Air Conditioning in Vermont.

Science Replaces Skepticism

For years, the EPA’s stance stalled the conversation, but new research is changing minds. Batchelder, who helped lead the recent energy study with Dr. Mark Hernandez, called the EPA’s shift a boost for “the academic side and other professionals,” and said it helps show that “the source removal method is really the best way to clean air ducts.” In that study, Batchelder said, “we found a 41 to 60 percent reduction in blower wheel energy consumption” and “supply air flow increased by 10 to 46 percent after cleaning,” with benefits observed in schools, offices, and other facilities.

The study, first reported by SNIPS News in February, Hernandez told us, “The question was, does cleaning the duct really help in terms of energy? And the answer is yes.” He explained that cleaning stabilizes system operations, reducing wasted energy and improving airflow consistency – critical benefits in energy and health.

But the research also highlights indoor air quality challenges. Hernandez noted that many schools shut down HVAC systems overnight to save energy, which leads to spikes in airborne pollutants when systems restart and resuspend settled dust. The study’s ongoing work in Denver Public Schools is measuring how cleaning interventions can reduce these pollution spikes and improve ventilation effectiveness.

Ethics Over Salesmanship

Both leaders are quick to stress that reputable contractors don’t just clean for the sake of it. Batchelder noted, “there are systems out there that probably don’t need cleaning. They are the exception, not the norm.” He added, “there have been times when an inspection warrants not cleaning or maybe just changing filters, or maybe it’s just the coil that needs to be addressed.”

McDavid saw the same in commercial and healthcare settings: “Many times I’ll get a call for a performance issue, or there’s debris on a register that they can see visually, and it has nothing to do with what’s actually inside the duct system,” he said. “Very frequently in the commercial industrial world, we will inspect the system and not recommend cleaning the ductwork because it wasn’t necessary.”

Source Removal: Raising the Bar

So what sets NADCA apart? For Batchelder, it’s technique: “The source removal method involves using large HEPA-filtered vacuums, connecting them to the ductwork so it puts the duct under strong negative pressure. Then, as we agitate the duct and air wash it, those contaminants get moved toward the vacuum, collected, and removed from the facility.” McDavid rejected shortcuts: “Once upon a time, 40 years ago, there may have been companies encapsulating things within a system. They weren’t actually removing it. We will never promote that type of program.”

Changing Minds, Raising Standards

Education remains a hurdle. Batchelder recommended sending skeptics to the Breathing Clean website. He said, “There’s a lot of information on there about why to clean ducts, proper methods. That’s really helpful for educating customers and contractors.” The campaign, he added, explains that “you can clean every surface in your environment except that air duct. It’s a hidden component … the Breathing Clean campaign really educates the consumer as to why we do a lot of the science, a lot of the procedures we do, what’s involved and why.”

Innovation, Measurement – and the Need for a True Safe Haven

Research is making the case for professional cleaning in schools, hospitals, and beyond. For healthcare clients, McDavid and Batchelder have seen how routine cleaning prevents contamination and protects vulnerable patients. For schools, Batchelder said, sensors now definitively show “a reduction in the particle matter in those classrooms where we performed duct cleaning.”

This emerging data underscores the importance of maintaining clean HVAC systems not just for energy efficiency but for occupant health – especially in vulnerable populations like children and patients. As the conversation ended, McDavid brought up a bigger issue: “The thresholds for indoor air quality don’t exist like they do for outdoor air quality, but you deserve to have a place to retreat indoors. You deserve a safe space. Everybody deserves that.”

With the EPA’s new guidance, Batchelder concluded, “validation through science is really going to help the industry with the old misconceptions about air duct cleaning.” For contractors and communities alike, the message is clear: when it comes to indoor air, the bar is rising.