Ionizing and ozone air purifiers have come under fire from consumer groups, consumer review magazines and even the Environmental Protection Agency (EPA). Two claims are at the heart of the controversy: that these types of air purifiers are not effective at removing contaminants from the air and that ozone generators could harm people. In 2002 and 2003, Consumer Reports tested several different air purifiers, including Sharper Image's Ionic Breeze. Independent researchers checked and verified the tests. Consumer Reports found that ionizing air purifiers like the Ionic Breeze created "almost no measurable reduction in airborne particles" [source]. Sharper Image sued Consumer Reports. The magazine later conducted further tests in response to Sharper Image's complaints and still found the Ionic Breeze to be ineffective. Sharper Image's lawsuit against Consumer Reports was thrown out, and the company was forced to pay more than half a million dollars to cover Consumer Reports' legal fees.

Gas vs. Electric Stoves: Which is really more efficient? Magnetic Air Conditioners: A High Tech Way Of Keeping Cool What natural gas home appliances are available? Should all of my appliances come from the same manufacturer? Is stainless steel on its way out? The EPA has also released information warning the public about air purifiers that generate ozone. Because the manufacturers are not making specific medical claims about these devices, they do not need Food and Drug Administration (FDA) approval. hepa air purifiers at targetIn fact, there really is no government oversight over consumer air purifiers other than the HEPA standard, so any manufacturer claiming that such a device is "government approved" or "government certified" is misleading consumers. radio ionizer air purifierHowever, concerns about the generation of ozone in people's homes have led the EPA to conduct studies on the subject.honeywell air purifier distributor in malaysia

All ionizing purifiers generate some ozone, but ozone generators are specifically designed to release the gas, and in much larger quantities than ionizing purifiers. The EPA states, "Relatively low amounts [of ozone] can cause chest pain, coughing, shortness of breath, and, throat irritation. Ozone may also worsen chronic respiratory diseases such as asthma and compromise the ability of the body to fight respiratory infections" [source]. Their studies indicated that even when used according to manufacturer instructions, many ozone-generating purifiers created ozone concentrations in a house in excess of public health limits. They also found that ozone as used in a household air purifier "has little potential to remove indoor air contaminants." They also noted that ozone has a tendency to react with chemicals and form by-products that are potentially even more dangerous. The EPA's final recommendation on the matter: "The public is advised to use proven methods of controlling indoor air pollution."

Ozone generators are not among the proven methods listed on its site.For years now Dyson has been the go-to company for impressively engineered (some would say over-engineered) air-moving devices. We all know of Dyson’s vacuums, Airblade hand dryers, and fans, but their fan family is more extensive than you might think. Fans became heaters and, as of September 1, they evolved into air purifiers. The Dyson AM11 Pure Cool air purifier is a tower fan (it’s 40 inches tall and meant to be placed on the floor) with a “360° Glass” HEPA filter that’s rated to last for six months of nonstop use. Tower fans are nothing new and Dyson does extensive air filtering with its vacuum line, so an air purifier — which is little more than a filtered fan — made perfect sense. For its part, Dyson would stress that adding in a filter is not enough to make an effective product. Poor design and construction means air leaks where tiny allergens (in the 0.5 micron range) can escape making any number of today’s air filters less than fully effective.

This puts us in the normal Dyson-decision-making mode: we know its a good product, but at $400 (list price) it’s not just expensive, its considerably more expensive than options we know to be great and two-to-three times more expensive than good products from reliable companies. As for me, I’ve used a Homedics AF-100 air purifier for years. I’d put it in the “better than nothing” category, which is to say that it has a street price of about a fifth of the Dyson and it seems to be sufficient for my needs. All that said, air purifiers that are designed for big rooms and serious filtration can get very expensive. At first glance, the Pure Cool is a Dyson “bladeless fan” with a new filter base. It looks a whole lot like the AM07 tower fan and the functionality is similar — it turns on and off, it oscillates, it runs at power levels from one through 10, and it can operate on a sleeper. The Pure Cool filter cannot be disabled or bypassed, but it can be removed and replaced.

It’s fine enough that it will filter out everything from bacteria to pollen to cooking smells. The key here is not just that it’s a good filter, but also that it’s sealed properly in the housing, which means the air being pushed through the fan went through the filter, not around it through a poorly fitted panel or leaky seal. In addition to offering Dyson-level build quality, the Pure Cool addresses another serious problem with air purifiers: they are ugly as sin. Most are beige plastic boxes that are embarrassing to have in any prominent place in your home. And hiding them away defeats the purpose of having an air purifier, because they need to be where the people are. The oscillation and power of the Dyson mean that it fits in a number of settings, and can sit in a corner and cool most areas. The fan does not tilt, but its height gives it enough vertical coverage for most situations when the fan function is as important as the air purification. One interesting complication with the Dyson bladeless system is that much of the air that is being moved never goes through the base or, for that matter, the filter.

Here is Dyson’s own explanation of the fan’s use of Bernoulli’s principle in its “air multiplication”: So, the majority of the air being moved by any Dyson fan, including this purifier, is not going through the base, so its never purified. This makes the Pure Cool seem like a product where Dyson’s bladeless technology might not be ideal. The Pure Cool was first released in China and Japan, and, like most air purifiers, is primarily aimed at markets where air pollution is a serious issue. This extends to the capturing of pollen, germs, and particulate, making it something with wider appeal but it’ll probably never be a big seller in the US or Europe. One thing I’m not going to do in this review is pretend to do any scientific testing of the air purifier’s filtration. If you want more on that I’d highly recommend SweetHome’s excellent dive into the science behind air purification. That article didn’t test the Pure Cool and ended up recommending a device that cost $250 — not cheap, but a far cry from the Dyson.

The only other thing I’ll note on this front is the HEPA is a DOE standard so there is quality assurance to the filters used by any company whose product uses that label. It doesn’t ensure that the fan quality will be good enough to take advantage of the filter, but at least you know you are starting from a strong foundation. At its very essence, what does a filter do? It takes stuff out of the air and holds onto it. After 25 days of 24/7 usage on setting four (out of 10) my Pure Cool’s filter picked up less than a tenth of a gram of particulate. I’d say that’s because I live in an immaculately clean apartment, but that’s not the case. And even if I did, the Dyson is less than 10 feet from a window, but was open for at least 5% of the testing time. I’m not fully sure what the takeaway from this is, but we do have to remember that when it comes to airborne particulate, a gram would be a lot. So you might never see additional weight if the filter was only picking up bacteria, but between things like dust and dander, I would have expect to see some movement, especially considering that this time period used up about 14% of the filter’s life.

What I really wanted to do was to find some way to prove the Dyson was doing its job. Once again, I’d point you at the SweetHome article or this video of the Pure Cool clearing the smoke from 10 cigarettes out of the air: Next was testing for noise production and air speed: For a bit of context you can check out the results from our testing of the best desktop fans (please note, that testing was done at a different time so it’s not apples to apples data). Long story short, the Dyson Pure Cool moves a reasonable amount of air, but it’s not a very powerful fan. As for the noise levels, I used an iPhone 6 with a noise monitor app, not any fancy test equipment. As a result, the numbers are inflated, but you can get an understanding of the trade off between moving more air and generating more sound. At its lowest three levels the Dyson is basically silent. At its loudest, the fan is more than you’d want to listen to in a typical living room but it’s not obnoxious — it’s along the lines of having a dishwasher or washing machine running nearby.

The final test was for power usage, which will help determine operating cost. The power consumption of the fan is relatively modest. If you were to run the Pure Cool at setting level five with oscillation nonstop for a year, your electricity cost would be $13.20 (at 15 cents per kWh). The price is the major drawback of the Pure Cool, but that’s pretty obvious from the start. There are some other downsides, but they are much easier to cope with. The filter can’t be rinsed, rather it must be replaced. Replacements don’t appear to be available for sale yet, but Dyson has said to expect them to be $70. At $140 for a full year of nonstop use (there is no mention of fan speed, but I’d assume this is at 50% speed), a more typical eight-hour-a-day user will have filter cost of about $47 a year. Not cheap, but more or less in line with the competition.  Another downside is the lack of a filter bypass. If you are using the Pure Cool as a fan and you have the window open or have it placed on a porch, you might want to use it without the filter so that you can minimize debris build up and maximum filter life.