Inside the Ductwork — Mold and Airborne Contamination Explained

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By Jules Lupowitz

This article is about the air you breathe where you live or reside.

People usually see the room-side grille or filter, not the interior of their ductwork. Photographs and footage from crews I’ve managed show another part of that picture: conditions before cleaning and the work in progress. In my experience, systems left for two or more years can show discoloration, accumulated dust and pollen, other debris, and sometimes insects or animal remains. The condition of a particular system needs to be inspected rather than assumed from its age.

Specialized skills and equipment are used to remove this debris. In the supplied footage, I describe a high-pressure air hose with automated circular brushing to loosen debris while a vacuum collection system captures it.

That is an account of this project. Different buildings, systems, and living conditions may require different inspection and cleaning approaches. The footage does not establish a particular health outcome.

The first useful question is what an inspection actually shows. A photograph cannot reliably tell viewers that a substance is mold, identify bacteria, or demonstrate that a particular cleaning treatment will improve breathing or reduce an allergy.

EPA’s consumer guidance recommends duct cleaning on an as-needed basis; it does not prescribe a routine one-to-three-year cleaning interval. It also emphasizes correcting underlying causes such as moisture. Its guidance does not support sweeping claims that duct cleaning cures or prevents health problems.

Reference: https://www.epa.gov/indoor-air-quality-iaq/should-you-have-air-ducts-your-home-cleaned