Ozone Generator vs Air Purifier

With all the literature and claims out there, it’s easy to get confused about the do’s and don’ts when it comes to air purification and ozone generation. In short, air purifiers work by mechanically capturing particulates (dirt, pollen, etc.) in their filters while ozone generators function by either disabling those particulates (at the molecular level) or effectively destroying harmful, organic material such as mold and fungi. Most importantly, an ozone generator is NOT recommended for everyday air purification needs… direct exposure to human lungs can cause irritation over time. Instead, they should be used for the following: ozone for cigarette smoke, stingy mold or just about any pesky odor that’s either hidden, hard-to-reach or just can’t be dealt with via traditional cleaning methods. Let’s dig a bit deeper on the most important differences between ozone units and air purifiers…

How They Clean the Air

Ozone Generators: As mentioned above, ozone (which is O3, basically oxygen with an extra oxygen atom) works by attaching an oxygen atom to chemicals, odors, mold, fungi, etc. That process is called oxidation and once attached, it changes the molecular composition of the pollutant, causing it to break down then ultimately harmlessly fall to the ground. In nature, ozone is naturally produced by an electrostatic process during rain or thunderstorms. That fresh and clean smell after a good storm is due to ozone (the word “ozone” is even derived from the Greek word for “smell”). Ozone machines efficiently replicate that process through either corona discharge or UV technology. Either way, the resultant ozone molecules are able to penetrate walls, carpet, fabric and more to fully and completely remediate even the nastiest and the most hidden pollutants.

Air Purifiers: Traditional air filters work in a more mechanical (physical) manner. Most units have two main components: a circulating fan and a series of filters. The fan is key in “feeding” as much as air as possible to the air purifier. The stronger the better as a greater volume of polluted air can pass through the filters per hour. Of course, the main downside is the noise. Most (poorly built) air filters have cheap fans that tend to be noisy at high speed settings. Modern models tend to use better and more efficient parts, dramatically reducing noise…which is critically important while trying to catch some ZZZs :). For example, we have the IQAir HealthPro in our home and, thanks to a blend of proprietary fan technology and sealed compartments, its motor is whisper quiet.

With respect to filters, most higher quality models have a series of progressively finer filter layers. First, is usually an activated carbon pre-filter which catches all the big stuff: dust, pollen, etc. It’s also critical in extending the life of the more expensive HEPA filters, which are next in the series. HEPA, which stands for High Efficiency Particulate Air, is a very fine filter mesh capable of capturing smaller particles such as finer dust and other chemical pollutants. They usually can’t capture bacteria, mold or viruses, as they’re just too small and tend to pass right thru. Some higher-end units attempt to fill that gap with the use of UV light during the air treatment cycle. Though the research is spotty on the effectiveness of UV during short bursts like that, there’s a good chance the UV helps kill the majority of microbes.

Wrapping Up

In our experience, ozone generators and air purifier units serve slightly different roles. Ozone should be used when you have a serious or untreatable smell or infestation (mold, fungi, etc.). And, remember, they should never be run with anyone inside. Once your shock treatment is done, open up all windows and let it aerate for a good half hour or so. Air purifiers are your prevention. Running 24/7, they’re a great way to prevent the need for ozone shock treatment (or at least increase the time between treatments). To maximize your air quality levels, we highly recommend you implement both. Sure, air purifiers are an ongoing electric and replacement filter cost, but you can’t put a dollar value on your health.

The Pros and Cons of UV and Corona Discharge Ozone Generators

Whether for residential or commercial use, ozone generators are used to remove and control a variety of odors. But how do you harness its power into a usable generator? Well, for the uninitiated, ozone is basically three parts oxygen (O3) and, outside of lightning strikes or other natural phenomena, there are two main ways we generate ozone: ultraviolet rays (UV) and corona discharge (CD). What are the differences between the two? Is one likely to be better for your specific needs? To help you decide, below are some key points to consider.

How do each produce ozone?

UV ozone generation occurs when light is passed over a UV lamp, which splits oxygen molecules, allowing them to reattach into ozone, O3.

CD ozone generation is accomplished by passing air through an electrical field (varying from low, medium to high frequency) and the electric current is what splits the oxygen molecules, which then creates the ozone, O3. Most CD ozone generators also have some form of cooling mechanism, usually air or water, since the electric current also generates heat.

Pros and Cons of UV Ozone Generators

A UV ozone generator is easier to clean, doesn’t produce nitrogen oxides and isn’t affected by the presence of humidity in the air (its major upside).

There are, however, a few important disadvantages associated with UV generators. First off, they don’t produce a high concentration of ozone. As a result, air needs to be exposed to the UV lamps for a longer time, thus it costs more to operate and, overall, they’re not as efficient as a CD unit. The minimum ozone production rate also makes UV technology difficult for certain commercial uses, including large-scale water treatment.

Another disadvantage of the UV ozone generator is its UV bulb life expectancy. While the unit itself may be less expensive, the UV bulbs can require yearly replacement with continuous use. Bulb replacement combined with the additional energy required to operate the unit results in (significantly) higher operating costs.

Pros and Cons of CD Ozone Generators

These days, corona discharge generators are quite commonplace both commercial and residential settings. It’s the preferred technology due to its ability to create higher AND quicker concentrations of ozone…giving it a much more efficient profile. By weight, CD machines can produce about 90% higher concentrations of ozone than UV. Not surprisingly, it’s also more cost-effective since it requires less energy at every ozone concentration level. With regard to long-term costs, its corona cell plates last much longer UV bulbs — on average, most consumers get over 10 years of high-yield use per plate, depending on the model (see our top-ranked CD ozone units).

Another important feature of CD generators is their size — smaller parts allow for greater flexibility, both is use and installation. With regard to cleaning, you’ll want to clean your CD generator every couple months to keep it at max production (less frequently if you use pure oxygen or a heated air dryer).

The primary downside of CD generators is that ozone production is affected by humidity. Just as static electricity is impacted by humidity, corona discharge can begin to slow down at humidity levels exceeding 60%. So, if you’re inside on a humid day, run your AC or other dehumidifying measures to get it below 60% and all should be well. If that’s not feasible, just wait for a better day. In over 10 years in the business, humidity issues have affected less than 5% of our customers, so while it’s something to consider, the majority of folks don’t ever encounter any humidity problems.

Bottom Line

Years ago, we had a decision to make — corona or UV. After running a variety of production (and cost) tests, it became increasingly clear CD was the way to go. From higher efficiency to longer shelf lives, we now recommend corona discharge units for all broad or specific applications, both commercial and personal. If you have any questions regarding CD vs UV, feel free to get in touch.