What is an ozone air cleaner ?
Ozone air purifier is a type of electronic air purifier which is frequently used to remove odors and sanitize (kill mold or mildew), and works by emitting ozone. Ozone is a powerful oxidant and is very reactive. Upon ozone emission from an ozone air purifier, the reaction between the ozone and gas particles takes place. As a result, new chemicals are formed, hence odors are removed. Since an ozone air cleaner works by emitting huge quantities of ozone, this type of air purifier is sometimes also called ozone generator.
Ozone Air Purifiers in-review – Is it safe and effective ?
Ozone generator is probably the cheapest kind of air purifiers to buy and maintain, hence it is quite popular. However, before you rush out to buy one, it is important to know that Environmental Protection Agency (EPA) has issued a warning regarding this electronic air cleaner.
In their reviews, this agency expresses concern on the safety of the use of an ozone generator at home. Now, you may think that ozone is good. While ozone is good when it’s in the stratosphere, it is not something you would like to have in our atmosphere.
It is because ozone is known as a respiratory irritant. So even at low concentration, as determined by EPA (50 ppb or part per billion), it is still something to be avoided, especially for people with respiratory diseases including asthma.
Many ozone air cleaner’s manufacturers claim that their air purifiers are safe and are well within the limit of EPA (50 ppb) if used in a room no smaller than the manufacturer’s recommendation. However, according to EPA there are still several problems with that:
- First, there are many customers who are not fully aware with ozone’s danger and put an ozone air cleaner in a much smaller room, hence increasing the ozone concentration to an unacceptable level.
- Second, the ozone level selectors in the ozone purifiers are not precise. For instance, although it says that such and such level should produce this much of ozone, in reality, the quantities of ozone emitted from the purifier are generally more than the intended levels.
- Third, EPA found that at the concentration acceptable to EPA, it actually does not work effectively.
- Fourth, the ozone is supposed to react with the chemicals in the room and in the process converts the existing chemicals into the new ones. EPA is concerned about this new form of chemicals because no one can even be sure that the new form of pollutant is not more dangerous than the previous one.
Based on those arguments, EPA suggested in their reviews NOT to purchase any ozone generator to clean air since there’s too much risk associated with it, and EPA does not see much effectiveness in removing gas particulates.
Indeed, initially, ozone generators were only used in the hospitality and/or restoration industry because it was cheap to buy and maintain. Its usage was only limited on rooms or houses where nobody was present. Remember, to be effective, the ozone quantities should be high and ozone is not safe in that quantities for both human being and animals. Hence, ozone air purifiers are only used, for instance, to clean up the smoke and odors of empty hotel rooms. It is also often used in restoration industries to remove musty smell from a flooded house, the smoke odors from a house that had been on fire, and so forth. In all application, after the cleaning finishes, the windows and doors are opened and rooms are left empty until all ozone has gone out of the rooms.
So you see, ozone air purifier is mainly used to get rid of smoke and odors in places not normally occupied for a while. It is important also to note that even at high concentration, it can only remove some gases/odors. It does not trap bigger particulates such as dust, pollen and many air-borne particles.
To address this problem, some home ozone air cleaner’s manufacturers add air ionizer into the machine. Hence you will have an ozone ionizer air purifier combo. Basically, what an air ionizer does is to ionize big particulates in the air. Once ionized, the particulates will literally fall down to the floor, and can be vacuumed. However, air ionization is not an effective way to remove particulates since the ionized particulates can also stick to the walls. In addition, even if the particulates fall down to the floor, they often lose the ionization, so they come back into the air again. Hence, the effectiveness of a combo ozone ionizer air purifier is questionable.
Suffice to say that the use an this electronic air purifier in a home setting where living beings are continuously present is controversial. Aside from the fact that it emits dangerous gas (ozone), its effectiveness in cleaning up the air is also questionable, especially if used at a concentration deemed to be “safe” by EPA.
So, if you ask us what the best ozone purifier is, we don’t have the answer because we can’t even recommend any ozone generator for home use.
So How To Remove Odors and Smoke Then ?
There are other methods by which an air purifier can remove odor and smoke without the danger of ozone emission. Since odor and smoke are basically gases, an air purifier with enough carbon or chemical absorbant will do the job. For a more thorough discussion on chemical and carbon air purifier,click here.
Otherwise, click here for more specific discussions on air purifier for smoke removal.