Allergy expert and Health Practitioner Mark Richardson answered the 10 most commonly asked questions when it comes to providing allergy relief with an air purifiers:
Which air purifier technology is best to relieve allergies? It depends on what kind of allergies you have. For seasonal allergies like pollen, and pet allergies, high efficiency particle arresting (called HEPA) technology is recognized by Doctors as providing the best relief. HEPA will remove airborne allergens to.3 microns, or 99.97% of all airborne particles.
How about allergies to Mold and Mildew? HEPA, while it will remove mold spores, will not kill Mold and Mildew. To kill Mold and Mildew you will want UV and Tio2.
How about Cat and Dog allergies? HEPA and a Pre-filter (a screen-like filter to catch hair and dust which also saves the life of the HEPA)
How about Dust allergies? HEPA, to gather dust, and a Pre-filter to capture hair and dust before the HEPA filter to help it last longer.
How about the Oreck model? The Oreck does not have HEPA and relatives solely on "electrostatic" or the positive and negative charge of some airborne pollutants so is not considered effective in my opinion for allergens. Most allergens do not have a charge so will not be captured in their "truman cells" as they call their plates.
How often should a person change the HEPA filter? It depends on the size of the HEPA filter but on average a good-sized HEPA should last 9-12 months under normal use. One thing to be wary of is the fact that many air purifier companies overcharge for the replacement HEPA after the initial purchase of the air purifier itself. So check replacement prices in advance. For a good sized HEPA filter look for replacements in the $ 30-40 range.
How long should it take to be effective? Assuming that you have the right technology to do the job several hours should be enough to notice a difference. Again this will depend on what you are trying to remove from your air. Mold and mildew can take 6-7 hours to clear
How much should a good air purifier cost? Because there are many overpriced units out there there is a good question. For a normal living room or bedroom I would not spend more that $ 300 for a multi-technology unit.
Should I run it all the time? To save electricity costs you might consider air purifiers that feature allergen and dust sensor. These sensors from Japan adjust the machine to the conditions in the room saving electricity and guesswork.
What do you recommend? For an affordable alternative to the typical 2-3 technology air purifiers, you can now find 9-technology air purifiers that include HEPA, UV, Tio2, Ion, Carbon, Electrostatic and more all-in-one by companies. I have a video review of some of these models, some of which include the new allergen sensing purifiers, available on YouTube via the link below.