One of the first things I learned when I hit the market to look for an air purifier is that it’s best to avoid air purifiers that produce ozone.
There are some air purifiers with ozone generators, while there are others with ionizers, which produce ozone as a by-product.
And if you ask any expert about it, they will likely recommend that you stay away from them.
This is because while ozone can make a room smell fresher and cleaner, it isn’t the best for our lungs.
But what if you already have an air purifier?
Is there a way to determine whether it’s generating ozone?
What does ozone even smell like?
Well, I’ll answer all these questions in this article.
When I researched to find the best air purifier for my needs, I had a hard time learning how to tell if the air purifier generated ozone.
That’s why I decided to make a definitive guide on it so that you won’t have to go through the same struggles when shopping for your air purifier.
So, read on to learn more.
What Does Ozone from an Air Purifier Smell Like?
The thing about air purifiers is that they can produce a lot of different scents.
While models with activated carbon filters do a great job of eliminating harmful odors, specific processes can result in your air purifier producing the foul odors themselves.
However, ozone isn’t your regular odor.
In fact, for a lot of people, it doesn’t even smell bad.
This is because ozone emits a scent similar to that of chlorine.
So, if you can detect an unnaturally “fresh” and “clean” scent in the air when the air purifier is on, that’s a sign of ozone in the room.
If the smell is faint and not too obvious, then the amount of ozone gas may not be dangerous.
However, if it’s very prominent and noticeable, there’s a high chance you have too much ozone in the room and don’t have the right air purifier for the space.
Why Do Air Purifiers Generate Ozone?
The main reason air purifiers generate ozone is because of ionizers.
There aren’t as many air purifiers with ozone generators on the market as they are dangerous, especially in closed settings.
However, that doesn’t mean that air purifiers don’t have other methods of generating ozone.
Even without a generator, air purifiers can generate ozone through an ionizer. Ionizers are great additions to air purifiers as they release negative ions that bind with particles in the air, causing them to fall to the ground.
With that said, the by-product of this reaction is ozone, which is why I would advise against ionizers with ozone generators.
Is Ozone Dangerous?
The CARB generally advises against getting an air purifier with an ozone generator.
The main reason is that ozone generators do not positively affect air quality.
Some people believe that ozone can help clean the air; however, all it does is give off a “clean” scent similar to chlorine which can trick people into thinking the air is cleaner.
However, this isn’t the only reason I recommend against ozone-generating air purifiers.
In small and enclosed spaces, inhaling ozone can be hazardous to humans and animals.
Ozone can cause lung irritation, which completely defeats the air purifier’s purpose.
With that said, you’re generally safe as long as the air purifier isn’t generating a lot of ozone.
If the scent isn’t overpowering in a room, then there isn’t much ozone.
But if the smell starts to get strong, that’s when you should start getting concerned.

What Happens When You Inhale Too Much Ozone
As mentioned earlier, the air must have a high ozone level before you start feeling the negative effects.
You won’t feel that irritated when there are low ozone levels in the air. At most, you might get annoyed by the chlorine-like scent of the gas.
However, when there’s a lot of ozone in the air, that’s when you should start getting concerned.
In fact, for some people, relatively low amounts of ozone can be enough to cause chest tightness, coughing, and other symptoms.
And when the ozone level is raised, the reaction can get even more intense.
Ozone poses the most danger for people with predisposed lung conditions.
Inhaling ozone can worsen certain conditions, which is very dangerous for some people.
And since ozone poses so many dangers, most people advise against getting air purifiers that give off ozone.
Should You Still Use an Ozone Air Purifier?
After doing all the research, I wouldn’t recommend getting an ozone air purifier.
Again, ozone won’t make the air purifier better at cleaning the air and doesn’t offer any benefits to humans.
Inhaling too much of it can lead to various problems that could have been avoided.
Most air purifiers won’t produce a hazardous amount of ozone. However, you always want to be cautious, especially if you have an existing lung condition that ozone can worsen.
So as much as possible, it might be best to get an air purifier that doesn’t generate ozone.
Most modern air purifiers don’t have ozone generators. So, you won’t have to worry about that.
However, there are still a fair amount of air purifiers with ionizers, which produce ozone.
While it won’t produce that much, if you want to stay as far away from ozone as possible, then stay away from these air purifiers.
Other Reasons Your Air Purifier Smells
One of the main complaints people have about air purifiers is their smell.
If your air purifier gives off a chemical-like scent similar to chlorine, it’s likely ozone.
However, there could be a high chance that this isn’t the smell you notice from your air purifier, especially if you made sure to get one without an ionizer.
So, what could be the reason for the other smells?
Well, there are a fair amount.
But in this section, we’re only going over the most common reasons your air purifier might smell bad or give off foul odors.

Old Filters
To start, old filters can cause air purifiers to smell.
This is especially true for people who opted for air purifiers with activated carbon filters.
With an activated carbon filter, the air purifier can absorb the gases and particles that cause foul odors.
This includes smoke, cooking odors, and more.
However, just like any other filter, activated carbon filters can get old and saturated.
When the filter is saturated, it won’t be able to absorb any of the odors anymore.
On top of that, it could even result in the air purifier releasing odors similar to what the carbon filter absorbed.
The best fix to this is to change your filters regularly to make sure that they don’t reach this point in the first place.
Bacteria, Yeast, or Mold
Another common complaint with air purifiers is that they can sometimes smell fishy.
The reason for this is bacteria, yeast, or mold developing within the filter.
This can also happen when filters are old, poor ventilation, and you don’t clean the air purifier.
If you want to check if there’s an infestation in your air purifier, you must take out the filter.
Once you do that, you can see whether or not mold and bacteria is growing in the filter that’s causing the foul odor.
Off-Gassing
If you bought a new air purifier, there’s a chance you’ll have to deal with plastic-like odors for a while.
This is because certain air purifiers can retain the scents that come about during different parts of the manufacturing process.
While these smells don’t last forever, they do release themselves when you have a new air purifier, which can be very unpleasant.
If this happens, you must be patient and bear with it first.
After a couple of uses, the off-gassing odors tend to disappear, and you won’t have to worry about them anymore.
If you want a quicker way of removing the odors, you can bring the air purifier outside, as the scents can escape faster.
I dislike the off-gassing scent. However, this is something you won’t be able to avoid with most modern appliances.
So, just be patient and wait it out.
The scent will disappear eventually.
Does My Air Purifier Smell Like Ozone? Conclusion
Ozone can be very dangerous, so you must ensure that your air purifier isn’t generating ozone gas unnecessarily.
Most of the modern air purifiers on the market don’t have ozone generators, but you can never be too sure.
The best way to notice is to check if the air purifier smells like ozone.
Ozone has a scent similar to chlorine, so if you notice a chemical-like scent that’s kind of fresh, this could be ozone and a sign that you need to take extra care when the air purifier is on.