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Air Ionizer Dangers: Are Ionic Air Purifiers Safe?

Air ionizers are designed to help provide cleaner air and they do this by utilizing ionized particles. But a lot of questions tend to come with the use of air ionizers, one of the most common being…Are air ionizers dangerous?

The Short Answer: It depends on who you ask. Some critics believe that air ionizers give off dangerous levels of ozone which is not only harmful to the environment, but can be equally as hazardous to your health.

air ionizer dangers - air quality
Ozone exists in 2 levels of the atmosphere: in the stratosphere (good – protects us from the sun’s rays) and at the ground level (bad – toxic when breathed in)

When inhaled in high enough doses, ozone can have harmful effects– including damage to your lungs, chest pain, coughing, or shortness of breath.

Because of this concern, federally-mandated standards restrict the amount of ozone any air purifier can give off. These restrictions help to ensure that any potential ozone exposure remains at a safe level.

Air ionizers vs. Ionic air purifiers

First things first, let’s get our names straight. In the air purifier market, there are air ionizers and there are ionic air purifiers.

Rabbit Air Purifier Filters
The Rabbit Air MinusA2 uses 5 different filters and an ionizer as the last purification stage

What’s the difference?

Basically nothing.

These are two different ways to talk about the same technology, electrically charged molecules being used to help purify the air. In this guide, we’ll be calling them air ionizers– so let’s continue.

How do air ionizers work?

A typical air purifier would use fans or filters to help remove contaminants and purify the air. In the case of air ionizers, they rely on the use of electrically charged air molecules, or ions, to do the same job.

RELATED – See our full list of air purifier reviews.

Every room is filled with positively charged particles, which could be made up of dust, microbes, odors, airborne bacteria or illnesses, smoke or other allergens.

The job of an air ionizer is to release negatively charged particles that are then attracted and bond to the positively charged particles in the room.

how air ionizers work

When the ionized particles bond to the airborne particles, the joint union is then too heavy to float in the air and they fall to the ground. Once they’re no longer airborne, these particles can be vacuumed up, or dusted off of furniture and raised surfaces.

What are the benefits of air ionizers?

Negative ions produce a number of benefits in our natural environment.

Think of some of your favorite places. Maybe it’s the ocean, a serene waterfall or out in nature’s greenery.

Ionic particles produced by waterfalls

This short list here includes some of the natural environments with the highest levels of detected negative ions present

Air ionizers and their connection to negative ions can mean big benefits to your respiratory system and overall health. The use of negative ions in the air can have the following results:

  • Improved air quality through the removal of dust, allergens, pollen, pet dander, mold spores and other airborne bacteria.
  • Decreased exposure to airborne respiratory bacteria like colds, flu, and asthmatic triggers
  • Improved sleep and overall mood, according to a 2012 Italian study that looked at the evidence base for the benefits of negative ions in improving mood and treating mood disorders
  • Relief from seasonal or chronic depression— according to a study from Columbia University, negative ions can have as much of an effect as prescribed antidepressants

All this sound too good to be true?

Some people would say yes. Let’s talk about the potential negative side of negative ions.

What are the dangers of air ionizers?

So naturally occurring negative ions are highly beneficial and share all of the benefits listed above. In the case of air ionizers, these negative ions aren’t naturally occuring, but instead are created through a method called “electric-discharge”.

air ionizer dangers - air quality

During the process of electric discharge, the negative ions that are produced may give off ozone, which can be a very harmful and toxic gas.

What is ozone?

Ozone is a colorless gas that exists in two levels of our atmosphere– one is good and one can be not so good.

air ionizer dangers - oxygen vs. ozone
Oxygen has 2 oxygen atoms while ozone is made up of 3 oxygen atoms, making it toxic for humans to breathe.

On one level, it exists in the stratosphere (which is approximately 6-30 miles high) and helps to protect Earth from the sun’s harmful radiation.

On another level, it also exists at the ground level, which is the air we breathe. Ozone in this part of the atmosphere is not good.

Ever see those ozone alerts as you drive down the highway or on the nightly news?

These are generated to let you know that ozone levels at the ground level may be reaching unsafe levels.

High ozone levels in the air you’re breathing can have really nasty side effects including damage to your lungs, chest pain, coughing, or shortness of breath.

Do air ionizers emit ozone?

So the million dollar question- do air ionizers emit ozone?

In short, yes they do.

Any man-made high-energy particle, like a negatively charged ion can generate ozone as a by-product of the molecular reaction.

Anyone remember the Ionic Breeze from Sharper Image? This product was one of the first air ionizers that came out.

Initially it was widely popular, but trouble came when third-party review sites began to question not only the validity of the air purification system, but also the dangerous levels of ozone that it was emitting.

SHarper Image Ionic Breeze air ionizer advertisement -1999 - source: The Hustle

What resulted from this product was a class action lawsuit, bankruptcy for Sharper Image in 2008, and revised federally-mandated standards (under the Clean Air Act) that put limits on the amount of ozone that a machine like this could generate.

Under these new regulations, the US Food & Drug Administration (FDA) required that indoor medical devices can only produce a maximum of 50 ppb (parts per billion) of ozone.

For comparison, the National Institute of Occupational Safety and Health (HIOSH) advises that indoor ozone levels be no greater than 100 ppb.

Air ionizers today are often fitted with ozone sensors that help to monitor, suppress, and prevent high levels of ozone from sneaking out into the air you breath.

The Bottom Line

Deciding whether or not an air ionizer is right for you is a personal decision. There are certainly benefits to air ionization that be difficult to achieve with a standard air purifier, but with those benefits also come potential risks.

Ozone is a real threat to our health, when consumed in high levels, but today’s air ionizers are federally-restricted in the amount of ozone that can be produced as a by-product of these machines.

At the end of the day, you have to decide for yourself and your family if the benefit of ionized air outweighs the potential risk of increased ozone levels.

Do your research, understand the technology, and move forward into a home with cleaner air.

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About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of He has been featured in Fast Company, Reader's Digest, Business Insider,, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

Need Help? Ask Your Question Below

  1. I have a pacemaker. Will the “electric discharge” interfere with my device? I’m not able to use a scale to weigh myself that measures the water weight because of the electrical current it uses…for example. Just trying to make sure I don’t harm myself while trying to improve my health.

    • Unfortunately, I (nor is anyone at Modern Castle) qualified to answer that question. You should pose that question to your doctor.

      But if you want to be safe, just don’t use an ionizer at all. HEPA purifiers are more than capable of air purification.

  2. Ions that are on a surface can prevent bacteria from growing. Basically, they can not process protein so there is no cell division and they die off. A virus is different but the ion approach still works. Glass, ceramics and Marble/Granite can all be ion exchanged to create silver or copper ions in and on the surface.
    So far, I have ion exchanged silver into/on glass. This produced a slight amber tint and the resulting silver ion surface was tested and certified to be anti-microbial. Awaiting results for anti-viral certification. The company I work for is offering this product for public spaces as sort of a contact barrier. Unlike plexiglass, glass does not scratch and can be cleaned easily. The silver ions are in/on the glass and do not come off as they are part of the glass (sodium comes out and is replace by silver as ion).
    The copper process is better as it is colorless and the ions reduce bacteria colonies faster than the silver ions.
    The company I work for does not do this on marble, granite or ceramics. Just glass and it required high temperatures to exchange ions in glass. On granite or other porous surfaces, heat is still needed but much less.
    I would suggest that if you are interested, research it. Many research documents exist. Works on metals as well but for that, easier to just use real brass or copper knobs on doors and such.
    Ions in and on surfaces are not an issue like ozone or other high energy particles in the air. There are many patents on the silver ion products but they are typically old and no longer enforced. Not all the processes that are patented work but the simple ones do work well, the complicated ones just make it harder to understand the simple method behind the process. The Romans and Greek used this back in the BC and AC times. It is not new and for many years, copper plumbing was the thing. Copper was and is a natural way to kill off bacteria,,, PVC, CPVC, PEX and all the other stuff just don’t do this.
    Do the research, there are safe methods that produce a permanent surface for anti-microbial and ant-viral properties that are safe for your families. Me, just a scientist that researches everything. Then figures out a way to get the same result in a very simple manner. I have quite a few patents for for how to make it better by making it simpler.

  3. I heard that cruise ships are starting to install ionizers on their ships to eliminate covid-19, is this not misleading passengers that this can guarantee to make the ship virus free? Do ionizers produce ozone and do they kill covid-19?

    • I don’t think any person, company, or brand can ever guarantee that any location is “virus free”. It’s just an impossible task, in my view.

      Most ionizers do produce ozone. However, commercial grade ionizers often include an ozone suppression systems. So it may be moot.

      Technologies vary as to how / if they deal with COVID-19. Some can, some can’t. You’d need to see what tests the manufacturer has completed.

  4. Is there anything on the market that still gives the “after a thunderstorm” clean air smell? I loved my old tabletop Ionic Breeze. I have purchased several air purifiers over the year but none of them give off that clean smell. The Ionic Breeze helped me sleep and controlled my rhinitis during the night.

    • There are. Any high powered ionizer will do that. However, it releases significant ozone in the process, which is not safe.

      One of the primary reasons Sharper Image is no longer around is because of lawsuits resulting from the Ionic Breeze, which created unsafe levels of ozone.

  5. I find it very interesting that everyone looks at Ionizers and is only concerned with ozone. Ozone is very harmful however, you can have an ionizer installed and it meet UL 2998 which basically states that no ozone is being produced by this product. No one is looking at the by-product of pumping a lot of ions into a space occupied by people. Those ions create hydroxyls which is part of Reactive Oxygen Species.
    It is well established that oxygen free radicals and their metabolites-collectively called reactive oxygen species (ROS)-can induce direct cell injury, which may trigger a cascade of radical reactions promoting the disease process.
    Lungs are vulnerable to endogenous and exogenous sources of ROS insults. They are well equipped with antioxidant defenses to negate normal oxidative insults. However, when the oxidative defenses are overwhelmed by formidable oxidant influx, injury results. Diseases are linked to this type of influx. Again I am not talking about OZONE. Everyone better get a good understanding on what happens when you introduce tens to hundreds of thousand of ions per cubic centimeter into occupied indoor spaces. ASHRAE 2019 9.4 clearly states that ionizers should not be used in occupied spaces.

    • Thanks for sharing your thoughts, Shaun.

      If the mere presence of a significant volume of ionic particles is really as dangerous as you are asserting then it would seem most regulatory and government bodies around the world have failed in their mandate to protect citizens.

      Why do you think these organizations are not recommendation disuse of all ionizers (even those that do not create ozone)?

  6. Derek,
    Thank you for your response. I will do that. I have also ordered an Ozone monitoring device to see how the levels vary. I believe that there are acceptable levels but for fixed periods of time.
    Thank you again for your quick response.

  7. I recently replaced all of my HVAC units in my house and had Air Scrubbers installed in each unit – 3 total – 2 on main floor – about 3500 sf and one in the basement – 1500 sf. I live in Phoenix so the units run quite a bit. The air scrubbers in installed are by AERUS model A1013P. When we leave the house for a bit and come back you can notice the smell of Ozone in the house. Is it safe to have these units running all the time and is 3 to many to run? Please let me know your thoughts.

    • If you are smelling ozone that’s not good.

      I would strongly suggest you get a professional air quality reading and make certain that the ozone levels are safe within your home.

    • Because of the COVID-19 pandemic and the continuous need for me and my family to go out & meet other people because of work, I’m now considering to purchase portable (necklace) air purifiers that is said to emit large amount of “healthy” negative ions. Do you think these have been tested vs producing ozone? Would you consider it safe to be exposed to such large amounts of negative ions (within your personal space) daily?
      I’ve tried to look for articles explaining the negative effects of being exposed to these kinds of devices for a long period of time and nothing much has come up.
      Hope you could share your views on this.
      I’m thinking of giving these to my family as a Xmas gift.

    • The idea that they are “healthy” ions seems to be a farce.

      I expect what they mean is that they don’t produce a large (if any) quantity of ozone.

      As far as if it’s safe, honestly, it’s an open question. To have these so close to your face and person would be concerning to me, especially at high volumes. While there is no definitive research (to the best of my knowledge) as to the safety or danger of this type of product, I would personally avoid these types of products.

      In my view, an N95 or equivalent facemask is more effective and we know with certainty that it is safe.

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