HEPA vacuum cleaners are becoming popular appliances in many homes to help control pet dander, pollen, molds, spores and other catalysts of allergies and asthma. HEPA vacuums are outfitted with industry-standard HEPA filters that prevent most particles from re-entering the room through the vacuum's exhaust.
Essentially, the HEPA filter works by intercepting and trapping very small particles that other vacuum cleaners would miss, and thus will help to maintain good air quality in your home. Historically, HEPA vacuum cleaners were designed to remove 99.97% of particles as small as .3 microns, and those standards still apply today. Of course, the vacuum must be able to filter all of the air that is drawn in if it is to be truly effective—those that can do so are termed "True HEPA" filters, and will come with a serial number to ensure its authenticity.
There are many varieties of HEPA vacuums available, including upright models, canister models and even HEPA central vac systems for the whole home. Here are the key features to look for when shopping:
Although both upright and canister models can be effective purifying tools, the upright models bring a greater risk of dust leakage than canisters. Moreover, canisters will generally allow for more mobility and will come with detachable vacuum tools to let you clean a variety of spaces and surfaces. But regardless of the style you choose, you will need to make sure that the filter bags are refreshed and the implements are kept clean in order for the machine to work at full capacity. A full bag will restrict air flow to the motor and in turn reduce the suction power by up to 80%.