I am sometimes slow to catch up. Although I had occasional wheezing over the years, I didn’t find out I had asthma until I was 30. And while air purifiers are widely recommended by almost everyone in the asthma and allergy world, I’ve never looked into them. Really a “purifier”? Sounds stupid.
But since I got one, my symptoms are a lot more manageable. And if you have allergies of your own (with or without asthma), consider getting one of your own. Right now, we are in the midst of asthma (spring) season, the time of year when indoor allergies, outdoor allergies, and seasonal colds can work with us. Your lungs have a lot to process; an air purifier can help.
What is an air purifier?
When you go shopping for an “air purifier” or “air purifier,” you’ll find plug-in units that sit in a corner of a room. They suck air in, filter it – ideally through a HEPA filter – and blow it out again. Tests by manufacturers show that these units do remove particles from the air, including pollen or dust.
That said, there’s one important caveat: There’s no conclusive evidence that air purifiers significantly improve people’s asthma or allergy symptoms. The EPA says they “may” improve symptoms, based on research showing small improvements. But we do know that they delete something from the air, and many people — myself included — anecdotally find that our symptoms improve when we have an air purifier on.
Last winter, it seemed like my allergy symptoms would kick in every time I went to bed. I had already wrapped my mattress, pillows and duvet in dust mite resistant covers, which helped. But then I thought I might as well buy an air purifier. Within the first day or two, those symptoms stopped before bedtime. Can I prove did the air purifier cure me? No. But will I continue to use it? Sure.
To get the most out of your air purifier, it helps to remember that you have other ways to keep allergens out of the air in the first place. Keep windows closed during pollen seasons if you have a pollen allergy, for example; be good with dusting and vacuuming if you have a dust allergy. We’ve got more tips for keeping allergen levels low here.
What kind should I have?
First of all, you should know that the kind of air purifier that is in the corner of a room is not the only way to clean your air. The American College of Allergy, Asthma, and Immunology recommends using a single room air purifier and/or a MERV filter for your entire home’s heating and ventilation system, if you have one. (If you only have central air conditioning but no heating, or vice versa, remember that the filter only helps whatever season the system is running.) The higher the MERV rating on your filter, the better; 13 must be minimum. Do not forget to replace the filter in time.
If you opt for a standalone (“portable”) unit instead or in addition, make sure it has a HEPA filter and note the CADR rating. CADR refers to the delivery rate of clean air, or how many cubic feet of air it can move per minute. Use this chart from the EPA to find out what CADR rating you need for a particular room. For example, a 10×10 foot bedroom is fine with an air purifier rated at 65 cubic feet per minute. But if you’re looking for something that can purify the air in a 600-square-foot area, you’ll want a CADR of 390 cubic feet per minute.
In my house we have a MERV filter on the central air system and I have a plug-in air purifier in my bedroom. It usually runs quietly, occasionally kicking in a sort of turbo mode when it detects more particles than usual in the air. There’s a light on top that I know I can turn off somehow, but I prefer the low-tech solution of draping a sock over it. And then there are the filters in it that need to be cleaned and replaced from time to time. I’m not very good at remembering to do that on schedule, but now that it’s peak week again, I think it’s time.