I moved into a new apartment a few weeks ago and noticed that it’s really dusty. I also hadn’t been sleeping so well, usually waking up with a stuffy nose. Maybe the air quality in here isn’t so good?
I started looking into air purifiers and they are EXPENSIVE! Like, $300 expensive, for a good one… in terms of price, the floor seems be at $150. Oof. So, can you make your own air purifier for cheaper?
What I found on the web:
- Here’s a cool video from UMich.
- As I dug around a bit more, I found this site, which has a blog with some good write-ups
- Here’s a test of whether DIY purifiers work.
- And the source for the design they test there
- Here’s an alternate design, that uses 2 filters and a bit of cardboard:
- Some things about making your filter efficient, regardless of which design you choose:
- Adding a fan shroud should improve efficiency
- Doesn’t really matter whether you put the filter on the front or back of the fan
- How close to the wall can you put it? (You can get pretty dang close without affecting performance!)
- And then a good analysis of whether you should keep your purifier on all day. The answer is that air quality is highly responsive to your purifier being on— if it’s on, your air quickly becomes clean, and then as soon as you turn it off air quality rapidly degrades. In this test, the air got to its resting “purifier running” state of air cleanliness in 20min; after turning it off, air returned to its resting “purifier off” state in 80min, but it got halfway there in 15min.
- This guy has also done some great experiments and is a doctor, if you care about credentials.
- And then this person literally just strapped some HEPA purifiers to a box fan… and it seems to have worked? They don’t even cover the whole back of the fan… but they measured particulate levels and it seems to have worked just fine. Confusing to me, but okay. Original post, HN post
What I did
- I ended up going over to Home Depot and buying
- Then I taped the filter over the front of the fan very carefully. You need to make sure it’s really airtight all around; Because the fan’s corners are rounded and the filters’ corners aren’t, I went over the fan corners first, leaving a gap near the fan body, then came back and did another layer of tape on each corner to seal it well.
- I added a fan shroud on the back with just duct tape
- I ran it all night with the fan on high and I really do think I slept better! I’m going to keep using it.