An Air purifier vs Ionizer – How They Compare

In the quest to ensure we have fewer or no allergens, pet danders, mold spores, and other airborne particles in our indoor air, consumers are often faced with the decision of choosing between an air purifier and an ionizer. Air purifiers and Ionizers essentially do the same thing. Ionizer is another word for Ionic air purifier. They are both air cleaners that improve the air quality in our living rooms and living quarters, ensuring fresh air and significantly lesser allergens. The differences between air purifiers and ionizers are in their different mechanisms, maintenance costs, and by-products.

What are Air Purifiers?

Air purifiers are technological devices that clean air. Air purifiers work to improve indoor air. They help to significantly reduce health risks for asthma patients and others with respiratory problems. Air purifiers with true HEPA filters are most preferred. Since Ionizers are the same thing as ionic air purifiers, we will now discuss both HEPA air purifiers and Ionizers as two types of air purifiers.

HEPA Air Purifiers

HEPA is short for High-Efficiency particulate air. For an Air Purifier to be certified as having a true HEPA filter, it must meet the criterion of having a 99.97% effectiveness. This means only three particles won’t be filtered out of 10,000. It also means that it is able to trap particles that are up to 0.3 microns. That is a really small size as the human eye can only see particles as big as 10 microns.

HEPA-type filters are also HEPA filters, less effective but still do an awesome job at 95%. HEPA purifiers are very effective in cleaning the air as they do air filtration, trapping mold spores, cigarette smoke, small particles, and other airborne contaminants between or within the filters, ensuring we have fresh air. Some HEPA filters are equipped with anti-microbial filters also so as to deactivate the germs that may be trapped in the filter. This ensures that the filter does not become a breeding ground for germs and makes the Purifier even more effective.


HEPA filters trap dust and other particulate matter. So, it is essential that they are changed from time to time so they do not become saturated and become sources of irritants and allergens. Don’t forget to carry out regular maintenance. If the filters are not changed, it is as bad as not having a purifier in the first place.

Uses of HEPA Purifiers

HEPA purifiers remove cigarette smoke, mold spores, dust, allergens, and irritants from the air, making it safer for asthmatic patients and others at risk of suffering respiratory ailments.

HEPA purifiers (carbon filter models) serve to remove moist smell and give the room fresh air.

Since HEPA Purifiers have very thin pore spaces that won’t let anything bigger than 0.3microns pass through, microbes are often trapped and prevented from harming people who breathe the indoor air. Microbes are of various sizes but many are bigger than the 0.3microns limit of HEPA Purifiers. In this way, HEPA purifiers may be able to protect you from harmful micro-organisms.


Air ionizers are also called ionic air purifiers. Ionizers work by using electric charges to purify the air. These are quite effective because they produce negative ions that bond with particles, making them heavy and dropping the air particles to the floor or to the collection plate in the Purifier. Ionic purifiers have had some trouble because they have often been confused with ozone generators. This confusion has also been fueled by Ozone generators who pass their products off as Ionizers.

Ozone generators produce Ozone in such large quantities and do not have collection plates, so they become dangerous to health as will be explained now. Ozone is only effective at high concentrations. However, such large quantities of Ozone are harmful to health and could cause respiratory problems, could irritate the lungs and affect you negatively. There is a list of health problems associated with ozone generation.

Ionizers vs Ozone generators

Ionizers and Ozone generators both produce Ozone as by-products but their difference lies in the safety levels and safety measures. Ozone generators have no collection plates and drop microbes to the floor. If disturbed, the microbes come up again, which means there was no use for the Ozone generator. Also, they produce very high levels of Ozone which are harmful to us. On the other hand, Ionizers produce negative charges which bond with particles and drop them onto the collection plates. As a by-product, Ionizers produce very low levels of Ozone which are perfectly safe and will not cause any of the symptoms listed earlier. The negative charges Ionizers produce also have the effect of deactivating microbes.

Maintenance of Ionizers

Ionizers have collection plates that must be cleaned from time to time to avoid the collection plates becoming some form of Petri dish for microbes. The collection plates do not necessarily have to be changed as they can last the entire lifespan of the Ionizer if washed regularly.

Uses of Ionizers

Ionizers clean air by binding to particles and deactivating microbes. They do not serve to clear the room of bad smell though.

Ionizers do an okay job in removing allergens and helping Asthma patients.

air purifier home screen

HEPA Air Purifiers vs Ionizers


High-Efficiency particular air purifiers are very effective at removing smells, small particles, and microbes due to the size requirement for particles to pass through which means only three (3) particles will escape out of every ten thousand particles. Ionizers’ effectiveness also depends on the homeowner. Ionizers that have charged collection plates can do a good job of holding the germs and particles, but they are still not as effective as the HEPA filter. So, it still largely depends on the homeowner to clean the collection plate and clean the house regularly.

Ionizers are also great at removing particles and germs from the air but they do not do as well when it comes to removing smells.

Maintenance costs

HEPA purifiers are generally more costly. This is as a result of the technology implemented. You also have to consider the cost of changing the filters regularly. Ionizers do not require that their collection plates be changed regularly. Just some good cleaning would do.

Purchase cost

Ionizers cost less than HEPA purifiers, costing about $50. HEPA air purifiers, however, range from between $50 to anywhere above $100. HEPA air purifiers use a more sophisticated technology than the Ionizer and that is why it costs more. You can make purchases or check prices on Amazon. We encourage you to go through Amazon, checking the different models and prices so you can make a choice on the one you can afford. If you are on a limited budget, perhaps an Ionizer is best for you since it does not cost as much as a HEPA air purifier does.

Design and Model variants

HEPA air purifiers come in different shapes and sizes. Some of the HEPA air purifiers are even mountable and come in various colors so you can choose the ones that match your fashion sense as an added bonus of having a HEPA purifier. Ionizers on the other hand, are usually cylindrical and have to be placed on the floor. There are smaller sizes that can be placed on desks or shelves but they are not as efficient as the bigger ones that are placed on the floor.


HEPA air purifiers do not produce by-products. However, Ionizers due to the negative charges, produce small quantities of Ozone which are still safe.


HEPA air purifiers make use of HEPA filters that ensure that particles and microbes with sizes up to 0.3microns do not pass through. There is absolutely no worry or controversy about this technology which is the product of multiple filters creating tiny pore spaces for air to pass through, trapping particles. However, there are concerns over the mechanism involved in Ionizers’ air cleaning. The negative charges produced by Ionizers create Ozone as by-products. Even though the little amount of ozone produced is not harmful in any way, Ionizers are victims of the Ozone problems caused by Ozone generators. So, many people stay away from anything that produces Ozone. Hence, many people stay from Air purifiers that have ionizers or that don’t have buttons to switch off their Ionizers.

Once again, it must be stated that the ozone levels produced by Ionizers are completely safe. As a matter of fact, the negative charges produced by Ionizers are good for the health and the environment. They improve air quality and your energy. It is important that you know that ozone becomes dangerous at over two hundred parts per billion (200 PPB). However, ionizers produce ozone at levels way below that. Ozone is safe when less than 50ppb (parts per billion).

With this, we see that Ionizers are actually safe. They are merely victims of the problems caused by Ozone generators.

These are the factors we believe are important and should be considered when making a choice between an Ionizer and a HEPA air purifier. If you are interested in comparing further, this is a table showing comparison- a table comparing Ionizers and HEPA air purifiers..


Both HEPA air purifiers and Ionizers are very safe. However, there is no confusion when it comes to HEPA air purifiers unlike Ionizers which are often confused with the harmful Ozone generators. Some producers also market Ozone generators as Ionizers. This then makes it safer to go for a HEPA air purifier unless you know what you are doing or you are buying from a popular and trusted brand, which then means you can go for either Ionizers or HEPA air purifiers. Keep in mind that Ionizers do not get rid of smells in your indoor space.

There is also the cost restraint on HEPA air purifiers which makes Ionizers a cheaper choice. If you are restrained financially, you might want to go for Ionizers. However, we recommend that you do proper research before getting Ionizers so you do not get Ozone generators instead of the harmless Ionizers you seek.

Whether you choose to get ionizers or HEPA air purifiers, do not forget to carry out the maintenance for your choice. Clean the collection plate in your Ionizer regularly, change the filters in your HEPA air purifier from time to time. Remember that the aim of getting these devices is to help clean air in indoor spaces and remove irritants and allergens from indoor air. That is the goal of getting these devices, not to turn them into reservoirs for the germs, irritants, and allergens you seek to get rid of. So, ensure that you carry out maintenance.