Air Purifier Buying Guide
11 Critical Factors to Consider When Buying an Air Purifier Choosing an air purifier or air cleaner for your residence or business can be a confusing task. There are literally hundreds of different models out there, and comparing one air purifier with another can be like comparing apples and oranges. Here are 11 factors to consider that can help you make the best decision for your environment:
1. Effectiveness (Particle Size Removal Capability) Most HEPA air filters (the most effective type of filter, not air purifier) can remove 99.97% of particles as small as 0.3 microns from the air. However, most microbials are smaller than the 0.3 microns a HEPA air filter is capable of removing (See Common Airborne Particles and Their Sizes in Microns). HEPA air filters can remove smaller particles, but not very effectively or consistently.
Electronic air cleaners that utilize negative ions (ionzier or ionic) and low-level ozone (negative ion generators and ozone generators) are able to remove particles as small as 0.01 microns from the air, which is smaller than many airborne pollutants, but not all. For instance, fumes and viruses are too small to be captured by any air filtration device. Oxidation ions can remove many of the fumes and viruses. Very few tobacco smoke particles are large enough to be captured by filters, but most of these are large enough to be removed by ozone, oxidation ions and carbon. Some dust mites and bacteria are large enough to be captured by HEPA air filters, but most (all bacteria) are able to be removed by ozone and oxidation ions. A HEPA air filter can capture most mold spores and pollen that pass through them, while ozone and oxidation ions can remove all that they come in contact with from the air, since they are emitted throughout a room or area.
2. Method of Purifying Air: Many air cleaners are hampered by severe limitations. Air cleaners that rely on filters, such as HEPA filters, can only clean the air that is nearby, leaving most of your house, or even a single room, unpurified. In essence, the unit must drag the entire room into the air cleaner unit in order to clean the air. Thus, only a very small percentage of the air in just a single room will find its way through a stationary filter. Plus, air filters can serve as a breeding ground for mold and bacteria. And the dust that is collected provides the mold and bacteria microbes the nutrients they need to thrive. Filters can also spread illness when you handle the filters for maintenance and replacement purposes because as you remove the filter, the mold spores, bacteria and viruses can become airborne.
Even if you eliminate a HEPA air filter from consideration, it is still important to realize that all negative ion, oxidation technologies and ozone generators are not alike. Due to maintenance requirements, many electronic air cleaners use a fragile glass plate that could easily break. Glass plate technology also means lower reliability due to the fragility of the glass plates themselves, and also because they need to be cleaned frequently in order to work properly.
There are three ways an air purifier can actively produce negative ions: By high voltage electricity run through metal needles (needlepoint ionization), or passively, as a byproduct of when ozone is created by corona discharge or UV light. However, negative ions have a very short life (2 - 6 minutes) and die before they can circulate completely throughout a dwelling. Also, a high-powered ion generator can produce what has been termed "black wall", a black dust that settles on surfaces, in particular around the ion generator.
3. Square Foot Coverage / Cost per Square Foot: A low price air purifier or air cleaner does not mean cost efficient. Many lower-priced air cleaners are actually costly when it comes to cost per square foot cleaned, the true measure of an air purifier's value. Most HEPA air filters are rated to cover 500 square feet or less, although they are typically similar in cost to oxidizer and negative ion air cleaners that can cover much larger areas.
To calculate the cost per square foot cleaned, simply divide the air cleaner's square-footage coverage into its cost. For instance, if the unit says it can clean 450 sq. ft. and costs $695, your cost per square footage is $1.54. Yet if it can clean 1000 sq. ft. for $399, your cost is $0.39 per sq. ft. You may also want to factor electricity consumption and filter replacement costs into your calculation to get a more accurate idea of "cost of ownership" and "true value provided". The Mammoth Air M1000x unbeatable filtration cycles the air for coverage up to 3000 sq ft of open space.
4. Whole-Home or Whole-Office Building Coverage: A single air purifier can rarely purify an entire home or office building regardless of how many square-feet it is rated to cover. This is due to the fact that walls, floors, ceilings, doors, etc. serve as barriers for air purifiers, even for those that use negative ions, oxidation and ozone.The best way to thoroughly purify the entire home is to use multiple air purifiers throughout the home, so each part of the home is within reasonable range of an air cleaner. However, this approach can be cost-prohibitive with most air purifiers. We do offer inexpensive Surround Air Ionizers and whole home Allergy, Asthma and Dust Furnace & Air Conditioner Filters. Turn your furnace or a/c into an air cleaner with our patented MERV-13 filters.
5. Replacement Parts Cost and Maintenance Many air purifiers will actually cost more in replacement costs for parts, such as filters, in a single year than their original purchase price. Be particularly aware of air cleaners that use air filters. Air filters generally last about three months, and in many cases cost a couple hundred dollars to replace. As has been mentioned before, ionizer air purifiers and ozone generators that use needles or glass plates require frequent cleaning and maintenance. Plus, the glass plates break very easily and often need to be replaced. Ceramic plates are much less susceptible to damage, but they are still vulnerable.
6. Strong Odor Removal If your primary need for an air purifier is to eliminate or reduce odors, then an air cleaner that uses oxidants, ozone or carbon will be necessary. HEPA and other air filters are not capable of removing most particles that cause odors, but oxidants or ozone can destroy most odor-causing particles and carbon removes them from the air. Negative ion-only air purifiers are not the most effective at removing strong odors either. They can help reduce odors to a degree, but are mostly effective at removing solid particles such as dust, pollens, animal dander, etc. If a negative ion air purifier also uses ozone, then it will be more effective at removing odors. But then you must be watchful that the ozone levels don't rise high enough to become an irritant. For odors, it is best to have an air purifier that automatically produces very low, safe levels of ozone so that the unit does not create harmful ozone levels that exceed safe levels (the EPS recommends no higher than .05 ppm).
7. Electricity Costs It is also important to find out how much an air cleaner will cost in power consumption, since some can cost over $300 per year in electricity. To determine annual electricity cost, find the number of watts listed by the manufacturer of the air purification system you are considering and use the following equation to determine the annual cost in electricity needed to run the air purifier.
(Watts/1000) X (KWH-Kilowatt Hours) X (8760) = Annual Electricity Cost
Example: Divide the number of watts listed by the manufacturer by 1000.
8. Noise Made by the Fan Many electronic air cleaners, HEPA and carbon-based air filters utilize a motor in an attempt to draw more air through the air filter because the only air that is treated in that which passes through the air filter. Unfortunately, these motors can be very loud. Many negative ion and ozone generators may also be equipped with a fan, but these fans usually make quite a bit less noise than a fan you might place on a desk in the middle of summer.
All air purifiers we sell have a quiet setting, making them virtually silent, especially at the lower settings. Brands that use a fan to distribute the negative ions and friendly oxidizers evenly throughout a room donīt need a powerful fan because negative ions and oxidizers can move around a room by using the roomīs natural air flow, due to their electrical reactivity with the elements of the air. The difference is that instead of dragging the entire room into the air cleaner to purify the air, they bring its purifying oxidizers to the air in your room, which also means that it doesn't take as long to purify the air in the entire room, as well adjoining rooms.
9. Warranty Most air purifiers on the market come with at least a one-year warranty. If an air purifier offers something less or no warranty at all, this should raise a red flag in your mind. The Mammoth Air M1000x comes standard with a 5-year warranty.
10. Size & Portability It is a good idea to buy an air purifier that can be easily moved from room to room. In which case, you should check the dimensions and weight of the machine to determine if it is portable. Plus, you may want to place your air purifier on a shelf or within a certain spot on an end table. This is especially true since negative ion and oxidant air purifiers are more effective when placed higher. In which case, make sure you buy a unit that is compact enough to fit in such places.
11. Guarantee Regardless of how wonderful an air purifier may seem from what you hear or read, you never know for sure whether it will result in a noticeable difference in your particular environment. Therefore, you should find a supplier that offers a money-back guarantee. This way, you will not be out a couple hundred dollars or more if the air purifier does not work the way you hoped it would. All products purchased from The Pure Air Store come with a 30-day money-back guarantee
See http://www.thepureairstore.com for products that pass our 86-point indoor air quality assessment standards. The Pure Air Store has tested and negotiated directly with each manufacturer for the best, most affordable air purifiers and air cleaners on the market!