
I’ve been having a rough time with the wildfire smoke the last couple weeks. Not full-on asthma attack bad, but definitely feeling tight in my chest, like I can’t get a full breath.
Indoor air purifiers help a lot. My criteria for a filter include:
- Needs to work well against smoke. Key words to look for: Filters particles smaller than 2.5 microns; MERV 13 (for furnace filters); and a high CADR rating for smoke. (Conveniently, this will also filter for viruses, as well.)
- It should not produce ozone – so no ionizers, no “electronic air cleaners.”
- It has to be QUIET, and it has to filter well when it’s on its quietest setting. When you see performance data, that assumes it’s on high. I have bat-like hearing, so the absolute loudness (decibels) and the pitch of the noise are very important to me. I’ve found 17 decibels is great; 23 is OK; and anything 40+ is hard to listen to for long. YMMV.
- I prefer things with fewer electronics, bells, and whistles that draw as little as electricity as possible.
- Filters should be affordable.
Here’s what I’ve found works for me (and no, I don’t profit from these links and I wasn’t bribed to say nice things about these):
- Blueair Pure Series
- Model 411 (discontinued) and 511, for small rooms like bedrooms and home office. On low, I can barely tell it’s on. On high, it will reduce the PM2.5 in my office from 25 to 10 in about 15 minutes. Consumer Reports said these are one of the only filters that do anything meaningful at low speed.
- Model 211+ (discontinued, but available on eBay – be sure it’s the 211+ or 211+Auto and not the plain 211). This is essentially the same as the 411, but for bigger rooms. It’s kind of large, but it can reduce the PM2.5 from 80 (unhealthy) to 20 (moderate) in a 12×15 room in about 15 minutes.
- Model 211i Max (new) – I’ve ordered this one, but haven’t received it yet. Basically, it’s the 211+ with some additional features, like a built-in PM2.5 sensor and phone app support. It’ll turn itself on when the air quality gets low and turn down or off when it gets better.
- There’s also a 311 auto that’s still in production that is larger than the 411 but smaller than the 211.
- A standalone air quality monitor is super helpful.
- Look for one that measures PM2.5 – smoke particles fall into this category.
- Note that the scale used for PM2.5 is different than the Air Quality Index (AQI) number you see reported on the weather. It’s nice if your monitor has both.

A couple key points:
- I’d rather buy a larger purifier and run it on low than buy a smaller purifier and run it on high.
- Check eBay for used purifiers. Watch the shipping prices, and expect you’ll need to buy a new filter from the manufacturer right away. I wouldn’t buy filters off eBay, though; it’s very little savings and there’s no way to know for sure the filters are unused and not knockoffs.
- You can’t cheat physics. Buying a purifier that’s too small for your space will help some, but it’s not going to have the power to do the job when the smoke gets into the “unhealthy” range.
- Focus on really, really cleaning the air in one or two rooms. Keep the door closed and crank it up. If noise is an issue, turn it up when you leave the room and down when you come back.
- These Blue models draw tiny bits of electricity – the 411 draws 2 watts on low – so just let them run all the time instead of trying to save electricity or filters by turning them off and on multiple times a day.
I’ll post later about some herbs that have also helped me during this time.