There are a lot of things to consider when you're shopping for air purifiers and other air treatment systems. Here are a few of the most important factors to keep in mind during your search.

Room Size

First and foremost, you will need to consider the space where your purifier will live. Will it purify a small space, a large room, or a whole house? What about a basement? Avoid paying too much by matching the purifier's capabilities size to size of the room.

Noise Level

Most machines are quiet and some are nearly silent. However, almost all create a bit of white noise. If you are using the purifier in a space where even a little noise will be an issue, make sure you choose a very quiet model.

Odor Removal

If you need an air purifier to take care of household smells get one with activated carbon. Activated carbon kills odors through adsorption. From cigars to cigarette smoke to pet odor; activated carbon is a must for odor removal.

Asthma and Allergies

Do you suffer from seasonal allergies or asthma? A purifier can help. A quality HEPA filter will remove almost anything that can trigger respiratory problems. Check out our comparison of the top purifier for asthma and allergies for more detailed information.

Clean Air Delivery Rate (CADR)

You'll see CADR in a lot of air purifier product descriptions and reviews. Bottom line; higher is better. CADR is a standardized AHAM rating applied to purifiers from major manufacturers. CADR measures purifier efficiency by calculating the volume of clean air produced each minute. The rating shows shoppers how much dust, pollen, and smoke a purifier removes from a 1,008 cubic foot room during a 20-minute test cycle. But, don't rely on CADR alone... our CADR rating article explains why.

Air Changes Per Hour

This is a much simpler metric than CADR, but important nonetheless. In fact, it's a major contributor to the air purifier's CADR. Simply put, it measures how much air a machine can move. You calculate air changes per hour by taking a machine's CFM (cubic feet of air moved each minute), multiplied by 60 (minutes), divided by a room's volume (in cubic feet). We recommend that you focus primarily on a purifier's features (e.g. HEPA, Activated Carbon). Not just how much air a machine moves or its CADR rating.

Efficiency

Electrical specifications, filter efficiency and amp hours, will easily bog down your search. However, we think an Energy Star certification is the easiest way to spot an efficient machine.

Filter Type and Maintenance

More often than not the right air purifier for most situations will feature a HEPA filter. But, you should also consider how often the filter will need to be replaced. How much it will cost to replace it. And, what kind of maintenance is required between changes? Filterless models are also available, for more information check out our filterless purifier review.

Customer Support and Warranty

Most products come with a warranty.There are a few manufacturers who offer limited lifetime warranties. But, we think you should look for a minimum of a three to five-year warranty.  Also, when we review a purifier we typically consider and include feedback from consumers regarding customer service experiences. Before you buy check the warranty and look into support experiences.

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Do you really need an Air Purifier?

You deserve fresh, clean air. Everyone does. Whether you live in an urban center, near a farm, or next to a factory... we're here to help you find the perfect air purifier for your home, apartment, or office. We're here to review anything and everything that improves indoor air quality. From budget-friendly filters to top-of-the-line, feature-packed purifiers. We even dig deep to find the best humidifiers, dehumidifiers, and random things that keep your home smelling amazing. Face the facts, you spend the majority of your time indoors. The EPA says the air inside a building is often much more polluted than the air outside. And, your home could probably use a little air circulation and deodorization, especially if you have pets. But, don't worry. We've been reviewing purifiers for years and we love to help families find new ways to improve the air they breathe. From huge homes to small apartments there is a top rated purifier for any space and budget. So take a look around or ask us a question in the comment section below! We're happy to help, and strive to be the best online purifier resource.

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What is an Air Purifier?

An air purifier is an appliance that filters various contaminants from the air indoors. Air purifiers are very popular in the homes of people who suffer from allergies and asthma, as well as in the homes of smokers and pet owners, but there is no reason that the average person cannot benefit from breathing cleaner air. There are many different contaminants that find their way into our homes, dust, pollen, pet dander, and mold just to name a few. Some of these particles float around in the air, while others accumulate on surfaces like couches, beds, and carpeting. To see evidence of this look no further than the dust on your nightstand. There are also chemicals, gases, smoke, and other odors that are present in our homes. Air purifiers can work to eliminate these things as well.

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How Does an Air Purifier Work?

Air purifiers work to remove these contaminants from the air before they accumulate. There are several different types, but they all operate on the same basic premise. The air purifier uses a fan to circulate the contaminated air through a filter or other device designed to collect the foreign particles before returning clean air into the environment.

Choosing a Size

There are several different sizes and shapes of air purifiers, and these things need to be taken into account when choosing the model that is right for you. There are larger models for those people with bigger homes who require more air to be purified, and there are also smaller compact models that are perfect for college students living in dorm rooms.

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The Different Types of Air Purifiers

There are a variety of different air purifiers to suit whatever needs you may have. The most apparent differences are in size and appearance, but the technological differences can be quite confusing. Some use simple filters, while others use complex technology originally used in space shuttles by NASA. The top air purifier often uses several of these different technologies within the same machine.

Air Ionizers

Air Ionizers do not utilize a conventional filter to purify the air. Instead, they rely on the generation of ions to magnetize contaminants in the air so they bind together and drop to the ground. This technology prevents contaminants from staying airborne, keeping them out of your lungs. Higher quality models will incorporate electronic rods or ceramic plates that are capable of catching the newly charged contaminants inside the machine. These plates can be convenient because they are able to be cleaned simply by wiping them with a cloth. The standalone problem with air ionizers is the controversy surrounding the health effects of ozone, which is produced during the ionization process. Experts say that those with breathing disorders should avoid ionizers altogether. Others regard ozone as a lung irritant. The catch-22 here is the ozone produced by air ionizers is what is primarily responsible for the crisp, clean smell that is loved by many consumers.

Ultraviolet Light

Ultraviolet lights are never used as a standalone component to purify the air. However, several manufacturers use this technology on the inside of their machines to eliminate germs, bacteria, and other dangerous airborne pathogens that can get trapped in the filters.

Pre-Filters

A pre-filter is commonly used as part of a three-step process in most HEPA machines. The function of the pre-filter is to trap as much large debris as possible, like dust and hair. This elongates the lifespan of both the carbon filter and the HEPA filter.

Carbon Activated Filters

Carbon Activated filters are not typically used to purify the air on their own. However, these filters are an essential complement to other air purifiers, especially HEPA models but also in some ionizers as well. In HEPA machines the carbon activated filter rests between the pre-filter and the HEPA filter. Carbon filters are effective because they have a unique chemistry that allows them to filter chemicals, gases, and odors in a way that HEPA or ionizers cannot accomplish on their own.

HEPA Air Purifiers

High-efficiency particulate air machines are almost universally agreed upon as the kings of air purification. Today HEPA filters find themselves in commercial aircraft, appliances, cars, and hospitals. But, scientists originally developed HEPA filtration as part of the Manhattan Project during WWII. And since then, they've only grown more popular, more affordable, and much more widespread. The United States government has set strict regulations for a filter itself to qualify as HEPA, in the sense that it must remove 99.97% of contaminants larger than 0.3 microns, which means that virtually all dust, pollen, mold, pet dander, and similar contaminants are effectively eliminated through the use of HEPA filters.

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There is a different type of air purifier to suit everyone’s individual needs. We are fortunate that a variety of models exist that utilize a variety of different technologies, to provide us with cleaner air to breathe. Hopefully, our air purifier reviews help you make an informed decision. If you ever have a question don't hesitate to send us an email or comment. If you'd like to learn more about what we do at passtaging.wpengine.com be sure to check out our story and philosophy. No matter what type of technology the unit uses, there are two simple tips you can follow to ensure the longevity of your machine. The first is to keep your air purifier clean. If you have an ionizer be sure to clean the plates off every so often. Replace filters if you need to. The second is to keep your machine clean. No matter what type of machine it is, it is almost a guarantee that getting water inside of it will affect its performance.