According to Dave Ford, president of DUCTZ of Central Mid-Atlantic Region in Baltimore, the average home generates about 40 pounds of dust per year, which tends to accumulate in ducts, returns and registers. An air duct cleaning, he says, can clear out the pollen, pet dander and microbes that tend to accumulate around the dust.
"Your home is a closed loop, and thoroughly cleaning your HVAC system can keep those microbes from recirculating," he says.
He recommends hiring a certified contractor who will address all parts of the system and not just vacuum out the ducts. "The most crucial part of the job is cleaning the air handler," he says. "If the coils and air handler aren’t cleaned, as you soon as you turn the system back on, the contaminants will just blow back into the home envelope."
Pogue, Paul F. P. 5 Life Hacks to Beat Seasonal Allergies. Web. 01 April 2016.