[Someone1234]

Just be cautious, while correctly working Air Ionisers are safe, poorly working or designed ones can produce Ozone which is unsafe (particularly over prolonged periods or high exposures). This article has more information (in particular citation 10 used in Adverse health effects):

https://en.wikipedia.org/wiki/Air_ioniser#Adverse_health_eff...

Personally I don't see the benefit over a HEPA filter on a standard electrical fan, or a commercial unit with a similar design. Yes, replacing filters is annoying/has a cost, but there's no health downsides to the design and it is effective at removing air particulate. Building one requires an off the shelf HEPA filter, an off the shelf fan, and a couple of rubber bands. It isn't "sexy" or technically sophisticated, but it works. Want it improve effectiveness? Increase the surface area/make it bigger/increase the airflow.

Let's also consider what both devices (when working correctly) do. An Ioniser gives particulate a charge causing it to be attracted to and stick on surfaces. A HEPA traps particulate within a filter membrane. Or to phase that differently an Ioniser causes the particulate to dust onto every surface within range, causing dirt buildup/stains, dust blooms when disturbs, and people may still contact the air contaminants (since they still exist, now on surface rather than in the air). HEPA allows you to simply remove the particulate from the environment, Ionisers just move it from one location (air) to another (surface).

[seltzered_]

Veritasium had a good video showing the test of ozone being produced by air ionisers: https://youtu.be/ZQ--scjcAZ4?t=663

(time-linking since the ioniser part was sortof hidden within a video debunking himalayan salt lamps)

[pergadad]

Thank you, really enlightening video. I'm happy I bought a HEPA filter now, rather than an ioniser.

[patcheudor]

In addition to the health concerns, ozone attacks unprotected polymers causing them to quickly break-down and release additional toxins into the air. I run an ESD ionizer at my well ventilated re-work / soldering station and have had plastic storage bins on the bench crumble at the touch from the ozone exposure.

[NickBusey]

This is especially ironic in this case, because the entire premise of the article was: "I have always had the issue of dust settling in every week on everything if I open the windows. Cleaning that up every week is a pain."

They then proceed to build a device that will, if anything, exacerbate this exact issue.

[arghwhat]

The issue was "I have always had the issue of dust settling in every week on everything if I open the windows."

If the dust is airborne, it will naturally spread everywhere before it eventually settles. Making the dust settle early minimizes spread.

[AstralStorm]

Ozone is actually a useful disinfectant, just make sure to ventilate the room well after treatment. Obviously not the outcome anyone building an ioniser is after.

[amelius]

Can't you collect the dust at a particular location by using an opposite charge?

[derefr]

> dust blooms when disturbed

I don’t find that at all. The dust that sticks to surfaces in my apartment can’t be moved even by forceful blowing on it. It has to be wiped away.

Also, I notice that when I brush stuck-on dust off a surface (e.g. my coffee table), it’s still ionized—so it just either gets pulled back to the sides of the table, or to the floor.

[raverbashing]

Another way of improving the homemade air purifier is adding an activated carbon filter (read: kitchen extractor hood filter)