Just how effective is duct cleaning? The answer is ....
After enduring years of advertising claims about the effectiveness of air duct cleaning — some of them outrageous and almost all of them unfounded in actual science — and after seeing it grow from a fledgling small business opportunity to a multi-million dollar industry, the Environmental Protection Agency (EPA) became interested in 1997.
The EPA decided to conduct a study on the effectiveness of air duct cleaning. The National Air Duct Cleaners Association (NADCA) had the opportunity to get involved in the “Pilot Field Study to Evaluate the Effectiveness of Cleaning Residential Heating and Air-conditioning systems and the Impact on Indoor Air Quality and System Performance.”