Ionic Air Purifier 101

Ionic air purifier is a type of air purifiers which works by ionizing air particles, hence the name ionic. Ionizing air purifier charge air particles with either positive or negative charges, with negative charges being more common and are even used to be thought to have positive effects on health.

Some ionic air purifiers send charged ions out of the machine, so they can attach themselves to air particles while others draw the air particles in and subsequently charge them. Either way, the results are the same. Air particles are charged or ionized.

A simple ionizer air purifier lets the charged particles to settle to a surface, ready to be wiped out by the home owner, whereas an electrostatic precipitator air purifier collects the charged particles in a series of metal plate collectors inside the machine. Hence, while a simple ionizer simply makes the airborne particles to settle because of the charges and does not do anything to actually remove the particles, an electorstatic precipitator draws the charged particles into the machine.

Do Ionic Air Purifiers Work ?

One of the most commonly asked questions in regards of ionic air purifier is whether it works. To answer this question, let's two different types of ionic air purifiers, the simple ionizer air purifiers and electrostatic precipitator air purifiers, and examine whether they are effective.

1. Simple Ionizer Air Purifiers - What Are They and Do They Work ?

An ionizer air purifier send ions out of the machines where the charged ions subsequently attach themselves to the suspended air particles. The charged air particles then neutralize themselves by attaching themselves to oppositely-charged surfaces, for instance, on the wall, carpet, and furniture, and settle there. Once they settle to a surface area, the air dust can be removed by simple wiping or vacuuming.

The question is: does this simple ionizer air purifier work ?

A simple ionizer whose job is just to provide charged ions can be said to work if it does the job properly. The better question to ask is therefore, whether a simple ionizer air purifier can actually clean or purify air.

Judging from the way they work, it is very unlikely that they are effective enough, especially if a machine only depends on simple ionization to clean air.

First, they don't actually remove the air particles from the room. They just move the suspended air particles from the air to the surface. Therefore, you still need to wipe or vacuum all the settled air particles off the floor or any surface. It is not uncommon for the home which use this kind of air purifiers to have a black wall phenomenon especially at places close to where the air purifier is located.

Second, those charges are very transient, which mean, those settled air particles can be airborne again if they lose the charges.

Therefore as a rule, a simple ionizer air purifier is not good enough to effectively remove airborne air pollutant. Even when it functions as an added technology in a HEPA air purifier, for instance, it's questionable whether it will add any substantial change over what a HEPA filter can do in an air purifier.

A more appropriate approach is by using an ionic air purifier which draw the charged particles in and collect them in a series of plate collectors. That way, those dust are removed from the room.

In this scenario, the ionizer releases partially charged particles which, in the presence of water vapor from the air, can turn into hydroxyl radicals. Hydroxyl radicals, like ozone, are unstable and highly reactive. They readily attack volatile organic gases, viruses, bacteria and other gases; either killing them or changing the chemicals into harmless air molecules. After the reaction takes place, the hydroxyl itself changes into water molecules. Therefore, unlike conventional ionizer which merely turn the suspended air particles into settled air particles, plasma technology really removes the air pollutant from the room by converting them into harmless chemicals.

The hydroxyl radical production technology or plasma technology is wonderful when used concomitantly with other filtration technologies, such as HEPA filtration since they complement each other well; HEPA being a superb filter for particles bigger than 0.3 micron, and plasma technology being an excellent fine-particle remover. In addition, as an oxidizer, they are very short-lived and unlike ozone, they won't hang out in your house for days. Therefore they are safe to use. By the way, this technology has been used in conjuction with other air filtration technology with good results by Plasmacluster by Sharp and Plasmawave by Winix.

2. Electrostatic Precipitator Air PUrifiers - Do They Work ?

Electrostatic precipitator is a kind of ionic air purifiers. In contrast to a simple ionizing air purifier described above, electrostatic air purifier actually collects the charged particles into a series of collector plates. Therefore, the air particles are removed from the room.

The question remains whether this kind of ionic air purifier works.

The effectiveness of this kind of ionic air purifier lies in 4 factors:

• Ability of the electrostatic air purifier to produce charge.
• The electrical field strength of the metal collection plate which ensure the degree of stickiness of the incoming charged particles to the collection plate.
• The total area of collection plate available which ensure it has enough space for all the incoming charged particle to stick to it.

Added to the equation is the fan speed of this ionic air purifier. In this respect, the manufacturer has to make sure that decent amount of air can flow through the air purifier, without it being too fast it cause the charged particles to not have enough time to stick the metal collection plate.

PRovided that the electostatic precipitator manufacturer fulfills those criteria well, this kind of air purifier should be reasonably effective to curb particles up to 0.1 micron.

For more discussion of the pro and cons of an electrostatic precipitator, click here.

Ionic Air Purifier - Are They Safe ?

Due to the high voltage required to produce electric field in electrostatic air cleaners, ionic air purifiers produce some amount of ozone. EPA gives a limit of 50 ppb ozone to any electronic device to ensure safety, but it is important to understand that 50 ppb of ozone is not background ozone and is not negligible. This means, that you will be able to smell the ozone and sensitive people may not be able to stand it. Ozone is a powerful oxidant and can irritate soft tissues such as our eyes as well as respiratory pathways. Lung sufferers, in particular, are better off not to go near to any of ozone-producing ionic air purifiers because of high possibility of respiratory pathway irritation.

Potential buyers need also to know that although EPA has set up a limit of ozone production, a small number of air purifiers do not follow this guidelines and yet, they still manage to find their ways to the residential air purifier market.

With all this information, does it mean you have to avoid ionic air purifiers altogether ?

We think that you should avoid ozone-producing ionizing air purifiers. Fortunately, there are a small number of ionizer which do not emit ozone or only emit a background/negligible amount of ozone. Online vendors or the manual can give you information whether a particular product is ozone-free.

Positive Aspect of Ionizer Air Purifiers

• No filter replacement required.
• Quieter than HEPA air purifier. This is because the unit breathes better, as opposed to a HEPA air purifier unit which has a filter barrier. Therefore, the fans of an ionizing air purifier does not have to work hard to push the air through the air purifier.

Negative Aspects of Ionic Air PUrifiers

• Many ionizers are ozone producing and therefore are not safe.
• Owners of electrostatic precipitator has to wash the metal collection plate often to ensure the continued effectiveness of the unit.
• Owners of simple ionizers which does not collect air particles, may not find the unit to be effective at all since ionizers just move the dust from the air to a surface and do not actually remove the dust from the room.
• In general, ionic air purifiers are less effective than HEPA air purifiers, unless the ionic air filtration technology is combined with the HEPA air filtration system. Otherwise, a pure ionic air purifiers can only, at maximum, provide all around cleaning and is very unsuitable to address people with problem, such as allergy, asthma, smoke, and so forth.

Related Articles

Summary of different home air purifier system or technology used to purify air.

Other technologies to purify the air:

• HEPA Air Purifiers
• Chemical and Carbon Air Purifier
• Electrostatic Air Purifier
• UV Air Purifier
• Ozone Air Purifier

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