On the packaging of air purifiers and air treatment devices, you will regularly encounter the term "ionization." Some devices have a separate ionizer button, while others use it as an additional function alongside filtration. But what does ionization actually do, and is it safe to use? We have set out the facts for you.
What is ionization?
With ionization, a device releases negatively charged ions into the air. These ions attach themselves to dust particles, pollen, and other floating particles in the room. Because the particles become electrically charged, they clump together and become heavier. They settle more quickly onto furniture, floors, and walls, rather than remaining suspended in the air.
Ionization is not filtration
An important difference from a HEPA filter: ionization does not actually remove particles from the air; it only makes them settle. The particles do not disappear; they move to surfaces in the room. With a true air purifier using HEPA filtration, particles are physically captured from the airflow and remain trapped in the filter, where you will not encounter them again.
Is an ionizer safe?
There is a nuanced answer here. Ionization itself is not inherently dangerous, but the process can generate small amounts of ozone as a byproduct, depending on the technology and the quality of the device. In higher concentrations, ozone can irritate the airways. This is a point of concern, especially with cheaper or older ionizers running at high power. Many people notice a light, tingling smell when using a poorly adjusted ionizer for a long time, which often indicates ozone formation.
Manufacturers of reliable devices keep ozone emissions within applicable safety standards, but not every device on the market has been tested for this. If you want certainty, check whether a device is explicitly certified for low ozone levels (for example, according to the CARB standard used in the United States).
Why most modern air purifiers do not use an ionizer
For these reasons, many manufacturers of modern HEPA air purifiers choose not to use ionization technology at all, relying instead on mechanical filtration. That is also the choice behind the Dynter AirPure Plus PA244: the device works with a HEPA13 filter that captures 99.97% of fine dust, pollen, bacteria, viruses, and microplastics, without adding ions or ozone to the air.
Advantages of filtration without ionization
- Particles actually disappear from the air instead of settling on furniture
- No risk of ozone formation as a byproduct
- Suitable for people with sensitive airways or asthma
- Less maintenance on surfaces, as no extra layer of dust forms on furniture
When can ionization be useful?
Some combination devices use a light ionization function as a supplement to filtration, for example, to allow larger particles to settle faster so that the filter can capture them more easily afterward. If this is carefully adjusted and the device is certified to have low ozone emissions, that need not be a problem. If you are in doubt, choose a device that runs entirely on filtration.
Our advice
For the health of your indoor air, we recommend choosing an air purifier that works with HEPA filtration instead of (exclusively) ionization. The AirPure Plus PA244 is an example of this: effective filtration without an ionizer, without the risks that can be associated with ozone formation.