Electrostatic Air Purifiers: What They Are & How They Stack Up

The air purifier market is extensive — so why not add electrostatic air purifiers to the mix?

In a market dominated by HEPA air filters and ionization air purifiers, electrostatic air purifiers offer an alternative that falls between the two main categories.

In some ways, it addresses their shortcomings. In other ways, it falls short in crucial categories.

Not sure whether you should cross off electrostatic air purifiers from your search? We’ll help you decide.

electrostatic air purifiers release ozone

Electrostatic Air Purifiers: What Are They?

An electrostatic air purifier is a device that uses a combination of both mechanical and chemical filtration methods at the same time.

Through the use of static charge and filtration, they aim to reduce airborne contaminants while requiring minimal maintenance and remaining affordable to upkeep. 

However, electrostatic air purifiers are not very common for residential usage when compared to the more popular HEPA and ionizer air purifiers due to efficiency issues and ozone concerns.

How Electrostatic Air Purifiers Work

Electrostatic air purifiers work by charging particles and pulling them through a magnetic field so that they’re removed from the air.

This process looks different depending on the type of mechanism the machine is using to charge particles.

The first method includes an air filter with an electrostatic charge and a mechanical collection plate.

When air is pulled through the filter, it receives a charge that is opposite to the other side of the machine.

The charge comes from the material used and can include an additional charge added during the manufacturing process for a stronger attraction to charged particles. 

Once the particle is charged, it becomes attracted to the oppositely-charged collection plate, where the contaminants can be removed manually during clearing.

In this application, you may need to clean or replace the charged filter over time so that it can effectively charge particles without blockages from built-up pollutants. 

You’ll also have to clean off the magnetic collection plate because a layer of particles can impact the charge of the collection, making it harder to maintain the plate’s ability to attract particles.

Alternatively, some devices will pull air through an electrical current to charge the particles before depositing them into the oppositely-charged magnetic field, where they’re easily collected.

This method requires no initial filter maintenance, but the collection plate will still need to be cleaned to ensure optimal performance, and the lack of filter means particles can accumulate more quickly, requiring more frequent cleanings.

Electrostatic Air Purifiers: Pros

Electrostatic air purifiers aim to be cost-effective, simple to maintain, and effective at filtering the air.

The cost-effectiveness of your electrostatic air purifier will depend on the type of purifier you choose.

Models with a charged filter may need to be changed once or twice a year, or they may be washable so that you can clear debris without ruining the electrical charge it holds. 

When compared to a high-grade HEPA filter, an electrostatic air purifier is cheaper to maintain due to its longer lifespan and potential reusability. However, they can cost more or cost the same amount as an ionizer that doesn’t use a filter.

Simplicity is another benefit of electrostatic air purifiers because their upkeep is minimal.

The particles that receive the charge are collected directly within the air purifier or trapped in the charged filter, allowing them to be easily accessible in a single location for simpler cleaning.

When compared to ionization, not needing to clean all of the surfaces in your room to remove pollutants can save time and effort. Plus, a simple vacuuming or wipe down of the collection plate or filter means you can get back to filtering your air sooner.

For performance, electrostatic air purifiers have the ability to address a wide range of particle sizes, including both large and small particles, because they don’t rely on mechanical filtration exclusively to remove pollutants.

Without the electrostatic element, air purifiers with filters need to be woven very tightly to ensure that small particles are addressed while static charges apply to even the smallest particles.

Electrostatic Air Purifiers: Cons

While there are a lot of convenient elements to electrostatic air purifiers, there are also a number of reasons that prevent them from being the first choice when it comes to air purification.

One of the major cons of electrostatic air purifiers is that they produce ozone.

Through the addition of a static charge to the particles, the charged particles are able to interact with the air to create ozone, a harmful volatile organic compound (VOC) that can be dangerous in high concentrations.

The concentration of ozone may also be increased near the unit’s collection plates, making it potentially harmful to place your electrostatic air purifier close to you.

Additionally, the performance of electrostatic air purifiers can begin to degrade very quickly when compared to other options.

As pollutants are removed from the air, the collection panels (and charged filter, if applicable) become covered in the various particles that they’ve removed, which affects the strength of the electrical charge. 

When this strength decreases, the unit’s ability to filter particles, especially heavier particles like dust and dirt, can begin to suffer, so you’d need to clean it regularly for the best performance.

With alternative purifier options, you can experience reliable, consistent air purification that helps you maintain high air quality with fewer variations in performance and less upkeep required.

It’s also possible that the pollutants that were removed by the air purifier can be reintroduced into the air during cleaning or as a result of a dirty internal filter, so you need to be careful when cleaning and keep on top of upkeep.

Electrostatic Air Purifier vs. HEPA Air Purifier

Some electrostatic air purifiers are similar to HEPA air purifiers because they use a filter — albeit in different ways.

In an electrostatic air purifier with a filter, the filter’s primary purpose isn’t mechanical filtration — it’s delivering the charge it holds to particles that travel through.

As a result, the filters are not tightly woven in an attempt to prevent particles from getting past, so they don’t do all that much to separate particles.

Instead, you’re relying on the collection plate’s variable charge to attract air particles and keep them on the plates for manual removal. 

A HEPA air purifier provides uniform air purification that does not vary as much in terms of efficiency as electrostatic air purifiers.

They’re generally able to generate more pressure to pull air through their highly effective filter of a predetermined size, ensuring that larger particles do not make it through the process. 

HEPA efficiency ranges from 80-99.995% on the first pass for particles as small as 0.1 microns, depending on the grade of the filter, every time air is filtered through, without dependence on your month-to-month cleaning cycle.

In terms of upkeep, electrostatic air purifiers have a clear advantage. Washable filters can be used for longer periods of time, while most HEPA filters will need to be replaced every 3-4 months. 

HEPA filters use multiple players of filtration to trap particles — many of which cannot be cleaned or reused — so you’ll need to dispose of them once they’ve been saturated in debris.

These regular filter replacements can end up costing more than the air purifier itself after as little as 2-3 replacements. 

Meanwhile, filterless electrostatic air purifiers have no maintenance cost at all, costing nothing more than the electricity they use, which is less due to the lesser power required to move the air through the purifier.

The downside is that they’ll need to be cleaned anywhere from monthly to each year, depending on the type of electrostatic air purifier you’re using.

Electrostatic Air Purifier vs. Ionizers

Electrostatic air purifiers are closer to ionizers than they are HEPA filters. 

Both options rely primarily on chemical filtration in order to clean your air, using electricity or a charged material to deliver a charge to airborne pollutants so that they stick to a material that can be easily cleaned.

As a result, both generate ozone through their purification process, which requires an additional cleaning device, such as an activated carbon filter, to make it usable in close proximity to you or your family.

But, electrostatic air purifiers release less ozone than ionizers so they may be safer for smaller rooms.

Despite similar mechanisms for delivering the charge that allows them to clean the air, electrostatic air purifiers and ionizers vary in the way that pollutants are removed from the air and the room itself.

An ionizer delivers an electrical charge to all of the particles that come through the filter, charging them so that they will attach to a surface in your home and can be removed.

There is no accumulation on the ionizer surface, so its performance is consistent. However, floors, furniture, walls, and various other parts of the room may attract these particles, which means a full cleaning of the room is required to remove pollutants fully.

Electrostatic air purifiers use a collection plate within the filter itself that is the opposite charge of the particles so that they accumulate on the surface. By trapping them inside the air purifier, it becomes easier to entirely remove them without committing to a lengthy cleaning.

But it also means your collection plates get dirty and vary in strength over time, so you’ll need to clean the plates (and intake filter, if applicable) more often.

FAQs about Electrostatic Air Purifiers

Does An Electrostatic Air Purifier Produce Ozone?

Yes, electrostatic air purifiers produce ozone when they deliver a charge to the particle that is being removed from the air.

Its interaction with oxygen molecules creates O3, also known as ozone, which is harmful in high concentrations.

Are Electrostatic Air Purifiers Better Than HEPA Air Purifiers?

The better choice between HEPA and electrostatic air purifiers depends on your goals. 

Electrostatic air purifiers are much less costly to maintain due to a lack of expensive filter replacements, but they’re also much less efficient, removing far less than the up to 99.995% of pollutants HEPA filters address.

Plus, HEPA has no ozone concerns – and even removes ozone and smells from the environment with the help of an activated carbon filter layer.

How Often Do I Need To Clean An Electrostatic Air Purifier?

Regardless of the unit’s method of charging particles, you’ll want to clean your electrostatic air purifier’s collection plate every month or so to allow it to work as effectively as possible.

For units with a charged filter, you’ll likely need to wash the filter every 3-4 months if it’s reusable or replace it every 9-12 months, depending on the manufacturer’s recommendations.

Are Electrostatic Air Purifiers Better Than Ionizers?

Generally, electrostatic air purifiers are better than ionizers when it comes to ease of cleaning and the production of ozone.

They make airborne pollutants easy to remove by collecting them in a single location, whereas ionizers send the particles throughout the room.

However, ionizers don’t get worse over time due to debris accumulation, so they can go much longer without cleaning.

The Verdict – Should You Buy An Electrostatic Air Purifier?

Overall, electrostatic air purifiers do provide some advantages when compared to their competition.

Through a combination of air filters and electrostatic charges, they work to address a wide range of particles with low maintenance costs and minimal upkeep that improves upon the high usage costs of HEPA filters.

They are also easier to clean than ionizers and put out less ozone, so that they may be safer for more compact areas.

However, consistency in performance can be a problem when compared to reliable HEPA air purifiers with high-grade filters.

Electrostatic air purifiers also require more unit supervision to ensure performance is at its maximum and can have a higher cost if they use filters when compared to ionizers that are set and forgettable.

If you’re looking for a lower-risk ionizer that’s cheaper to maintain than HEPA air purifiers but doesn’t work as well as a high-grade HEPA filter, then an electrostatic air purifier may be worth giving a try.

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