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Comment by marginalia_nu | Hacker News Reader

It's not like it's impossible to remove odors with chemical means. A very concrete example: The way lingering smoke damage is treated after scrubbing off the soot is with ozone. The smoke smell is from volatile partially oxidized hydrocarbons, and ozone just loves getting rid of an oxygen molecule and becoming O^2.

It's at least conceivable that there would be less noxious options available than ozone. An old trick is to use vinegar, seems to work.

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Ozone is extremely powerful, there are various "air purifiers" that emit small amounts of it and they do work --- as long as you don't use too much, since ozone also attacks plastics and other things you don't want destroyed along with the odourous chemicals.

Ozone is toxic to humans. You don't want too much because you will literally die.

I am highly doubtful that ozone in safe concentrations will do anything. Even at unsafe but not immediately threatening concentrations it probably does nothing.

My parents had an ozone-producing air purifier when I was a child. I liked the smell, and I thought the ozone was healthy (nobody ever told me otherwise!), so I had the habit of turning the ozone knob all the way up, sticking my face in front of it, and taking deep breaths.

It didn't cause any health issues as far as I know, but in retrospect, I really wish regulators and/or my parents would have prevented that from happening.

I did the same thing! I'm still fond of that smell!

If you can smell it, you're using too much (unless you're actually doing a "fumigation" where you turn it on for a set time, leave the room and close the door.)

I don't know about the US, but in the EU regulators DID step in and limited amount of ozone that can be produced by consumer devices to relatively safe levels. It will smell like thunderstorm but shouldn't be too toxic.

According to wikipedia, california limits to 0.05 ppm and the more sensitive people start to smell it at 0.1ppm.

So if you can smell it, that's probably not great.

I don't think you can smell ozone - it's rather noxious. I think what you can smell as "thunderstorm" is the air cleaned a bit by ozone and the process of ionization (which traps some bigger particles).

It largely gets captured in the mucus barrier in the lungs, but people with COPD or asthma also tend to have poor barrier function (Both mucus and lung liner) so it leaks into the blood stream easier.

I would stay far away from Ozone, dangerous AF.

> Relatively low amounts of ozone can cause chest pain, coughing, shortness of breath and, throat irritation. It may also worsen chronic respiratory diseases such as asthma as well as compromise the ability of the body to fight respiratory infections.

Just pick up a vivosun carbon filter on Amazon for $100, they're ugly as dirt and made for people growing weed - but turn it on for an hour or so and it'll remove most VOCs (smells, gasses, etc.) and particulate in your air. Problem solved.

How would those compare to using a box fan and square HVAC filter with activated carbon? HVAC filters can be purchased for a lot cheaper than $100.

The replacement filter (4in by 14in metal can filled wih activated carbon) is only $38. The up-front cost $100 is the price of the filter, plus a cloth filter which goes around it, and the duct fan.

From what I understand, activated carbon works really well for both particulate and VOCs but, unlike say HEPA filters (or non-HEPA cheap HVAC filters), it cleans the air after many cycles. So the amount of air passing through it, and how many times it passes through it, matters a lot.

I think HVAC activated carbon filters are likely to let more particulate get to your HVAC unit, which is not good for it, and will not clean as much due to HVAC not moving as much air as these portable units.

But I'm just an amateur airhead.

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