Allergies, Asthma, and the Filter on Your Wall
For the millions of people who live with allergies or asthma, air filtration isn’t a convenience — it’s a medical necessity.
More than 50 million Americans experience some form of allergic disease each year, making it the sixth leading cause of chronic illness in the country. Asthma affects over 25 million people. For both groups, the indoor environment — and the air quality within it — is a critical variable in managing symptoms and preventing crises.
The triggers most commonly responsible for allergy and asthma episodes indoors include dust mite particles, pet dander, cockroach allergens, mold spores, and pollen tracked in from outside. All of these are airborne particulates, and all of them are captured by a properly rated air filter in good condition. The HVAC system, in this context, functions as a whole-home air purifier — provided its filter is doing its job.
Choosing the right filter for allergy and asthma households is important. Standard fiberglass filters with low MERV ratings catch large particles but allow fine allergens to pass through freely. Pleated filters rated MERV 11 or higher offer substantially better capture efficiency for the particle sizes most relevant to allergic response. For households with severe allergy sufferers, HEPA-grade filtration — either through a HEPA filter compatible with the existing system or a supplemental air purifier — can provide an additional layer of protection.
“During high-pollen season, a well-maintained high-MERV filter in your HVAC can reduce indoor pollen counts by more than 90 percent.”
It bears emphasis that even the best filter is ineffective if it is not changed regularly. A saturated filter not only fails to capture new particles — it can also begin to release previously captured allergens back into the airstream as it becomes compressed and damaged. For allergy and asthma households, filter maintenance is not optional maintenance; it is ongoing medical management of the home environment.