Unlike anti-dust mite devices, which target dust-mite allergen reservoirs using mattress and pillow encasements, humidity control, hot washing, high-efficiency vacuum containment, or other defined methods rather than directly treating asthma or allergy, hepa air purifiers draw room air through high-efficiency particulate filter media.
The categories separate most clearly through different mechanisms. For hepa air purifiers, examine hepa media and clean-air delivery; for anti-dust mite devices, examine mite reservoir and encasement. Conveniences can be compared after the decision has a concrete goal.