Do HEPA filters help keep dust out of the air?

Question: I'm worried about my vacuum stirring up a lot of dust when I clean. Will HEPA filters help keep dust out of the air?

Answer: A vacuum cleaner equipped with a high efficiency particulate air (HEPA) filter can be effective for people who have problems with airborne allergens and irritants such as animal dander, pollen and dust.

HEPA filters attached to vacuum cleaners reduce dust by trapping small particles and not re-releasing "dirty" air. Effective HEPA filter-equipped vacuums require enough power to draw up all dirt and allergens, and need to be airtight to ensure that the smallest particles don't escape. Regular vacuums redistribute the same dust, dirt and allergens sucked from carpets back into the air.

HEPA filters are also designed as freestanding units that trap airborne allergens, such as pollen and animal dander. Many people with allergies have a freestanding HEPA filter in the bedroom, a HEPA filter-equipped vacuum or both. Filters need to be changed regularly on freestanding units and vacuums.

People using HEPA filters say they feel better and have reduced symptoms. And studies do show some reduction in the amount of cat and dog allergens with the use of the filters. However, to date, the majority of clinical studies do not prove conclusively that HEPA filters result in reduced medication use.

Neither filtering device, however, is a substitute for standard medical treatment. For pet allergies, the best defense is still reducing exposure to pets, keeping the dog or cat out of specific rooms.

For non-airborne allergens, such as dust mites, encase pillows and mattresses. It is also important to frequently wash bedding in hot water (130° F).

This information has been approved by Hal Nelson, M.D . (June 2006).