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Air quality is integral to good sleep. Unfortunately, a wide assortment of contaminants – including dust mites, volatile organic compounds (VOCs), and microbes like bacteria, viruses, and mold – are commonly found in bedrooms. To cleanse their sleeping areas of contaminants, as well as unpleasant smells, many sleepers turn to air purifiers. These devices can benefit sleepers with allergies and asthma, as well.
Air purifiers rid rooms of contaminants using either active purification, which converts chemicals and gases into harmless molecules; or passive purification, which extracts contaminants using a built-in filtration system. Most air purifiers sold today fall into five categories based on their design: HEPA (passive), activated carbon (passive), ionizer (active), ultraviolet germicidal irradiation (active), and ozone (active). Additionally, some models utilize two or more of these systems simultaneously. Our research indicates that purifiers with HEPA and/or activated carbon filtration systems tend to produce the best results.
This guide will explore the pros and cons of different types of air purifiers, and also includes our picks for the best air purifiers sold today. Our choices are based on verified customer and owner experiences, as well as intensive product research and analysis.
Our Editor’s Pick is Molekule, an air purifier that uses nanotechnology to purify particles out of the air that are up to 1,000 times smaller that what HEPA filters can catch. The Molekule purification system uses two filters: a “pre-filter” that captures larger particles like dust and hair, and a filter that breaks down pollutants at a molecular level. The second filter uses Photo Electrochemical Oxidation (PECO) technology. PECO uses light-activated free radicals to oxidize pollutants. While other air purifiers filter unwanted particles out of the air, the Molekule literally destroys them. It can destroy particles that are too small for HEPA filters to trap, such as airborne chemicals, bacteria, viruses, and mold spores.
The Molekule is at a higher price point than many air purifiers at $799. The Molekule runs quietly and is more energy efficient than many air purifiers. It is portable and cylinder-shaped, which allows it to clean air equally from all directions. It works well in larger rooms and can completely replace the air in a 600 square foot room in one hour. The Molekule comes with a 60-day trial period and 2-year warranty.
The LV-PUR131 from Levoit is a cutting-edge purifier that utilizes two types of active purification – HEPA and activated carbon filtration – to rid bedrooms of more than 99% of allergens, dust mites, and mold spores. This purifier is highly effective at eradicating odors, as well. The LV-PUR131 covers up to 322 sq. ft., making it suitable for most living rooms and large bedrooms, and will completely purify the air within 10 minutes or less.
The purifier also features one of the most advanced timers available; it is adjustable anywhere from one to 12 hours, and can also be set for a quieter sleep mode. Three fan speeds are available. The LV-PUR131 also has a built-in air quality monitor that indicates when more purification is needed.
The LV-PUR131 is widely sold for less than $160, making it cheaper than many competing air purifiers with comparable functionality and coverage. Amazon Prime members qualify for free shipping, as well. This purifier is backed by a two-year warranty.
In terms of purification coverage, the Airmega stands alone. This model comes in two sizes based on coverage area: the Airmega 300 covers 1,256 sq. ft.; and the Airmega 400 covers 1,560 sq ft. Both models are suitable for living rooms, bedrooms, and most other rooms found in today’s homes, as well as garages. The Airmega utilizes a HEPA and activated carbon filtration system that eradicates up to 99.97% of allergens, mold, and, dust. It also offers three purification modes: auto, eco (which conserves the fan in relatively pure rooms), and sleep (which is much quieter).
The Airmega had four speed settings, as well as a time that can be set for one hour, two hours, four hours, or eight hours. It also has a built-in air quality monitor with a crisp, easy-to-read LED display, and a ‘filter life time indicator’ that tells owners when to swap out the filters.
The Airmega 300 is widely available for roughly $400, while the Airmega 400 is usually priced closer to $570. Amazon Prime members qualify for free shipping when they order either Airmega purifier. Both models are covered under a five-year warranty.
Our Best for Pet Dander pick is the MinusA2 from Rabbit Air. This purifier features an active purification system with a HEPA and activated carbon filtration system, which eradicates allergens such as dander and dust mites using a six-phase purification process; this makes it more effective than most conventional filter-based purifiers. The MinusA2 is available in two models, each with different coverage areas: the SPA-700A can cover up to 700 sq. ft.; and the SPA-780A can cover up to 815 sq. ft. The SPA-780A is also available in an advanced, WiFi-compatible design that connects to smartphones and other iOS devices.
The MinusA2 has five different speed settings, outnumbering many competing models, and will automatically adjust to sleep mode when placed in darkened rooms. The purifier can rest on the floor or be mounted on a wall, as well.
Prices for the MinusA2 start at $550, making it a good option for shoppers with bigger budgets. Amazon Prime members qualify for free delivery options. The Rabbit Air MinusA2 is backed by a five-year warranty, which is much longer than average compared to other air purifier warranties.
The Airocide APS-200 is a filterless air purifier with a unique, attractive design. It has a rectangular shape with a cut-out in the middle. A fan draws air into the cut-out area, then that air is oxidized using a NASA-created process called photo-catalytic reaction. This technology allows the Airocide APS-200 to purify particles that are too small for a HEPA filter to trap. Unlike HEPA filters that trap pollutants, the Airocide APS-200 actually destroys them. This air purifier can eliminate volatile organic compounds (VOCs) from paints, cleaning products, air fresheners and more. It also destroys germs and common allergens, such as pet dander, mold, and dust.
The Airocide APS-200 costs $699, making it more expensive than many air purifiers. It comes with a 60-day trial period and a 5-year warranty. This air purifier can be used in small or large rooms. The Airocide APS-200 takes up less space and uses less energy than many other air purifiers. Although it doesn’t use a traditional filter, the Airocide APS-200 does contain a reaction chamber that must be replaced yearly. The cost of this piece is $139.
At 3.5 pounds and less than 18 inches high, the Blue Pure 411 from Blueair is one of the smallest air purifiers on the market. Its coverage area is smaller – roughly 100 to 175 sq. ft. – but the device uses a combination of HEPA and activated carbon filtration that will eradicate 99% of allergens, dust mites, and other contaminants from any small to moderately sized bedroom. It is also effective at minimizing odors. Three fan speeds are included, as well as a non-adjustable timer.
The Blue Pure 411 also produces relatively little noise, with a volume range of 17 to 46 decibels; most larger purifiers are at least 50 decibels at their quietest. It also produces five air exchanges (or filtrations) per hour, which is on par with higher-coverage models.
The Blue Pure 411 is widely available for less than $90, making it a high-value pick. It is backed by a one-year warranty.
A bedroom’s air quality is important for getting a good night’s sleep. Many people rely on air purifiers to rid their sleeping quarters of dust mites, microbes and other airborne particles, as well as bacteria, viruses, volatile organic compounds (VOCs), and unpleasant odors. Air purifiers are particularly beneficial to people with allergies and/or asthma. Air purifiers sold today fall into four general categories based on the type of filtration used: HEPA, activated carbon, ionizer, and ozone; some purifier models utilize more than one of these systems, as well as UV technology. Although high-end air purifiers can cost hundreds of dollars, shoppers can usually find models for $100 or less.
This guide will explore the purpose and functionality of air purifiers, some benefits and disadvantages of using one, tips for first-time buyers, and our picks for the top-rated air purifiers according to actual owners.
Air purifiers remove contaminants and irritants from indoor air using one of two general techniques:
Most air purifiers sold today utilize one (or more) of the following four technologies:
HEPA: An acronym for High Efficiency Particulate Air, HEPA is a filtration system that must (according to industry standards) trap at least 99.7% of particles larger than 0.3 microns, which include chemicals, spores, and other particles that cannot be seen with the human eye.
HEPA filters are accordion-shaped and made of ultrafine fibers. They use four processes to trap particles of different sizes:
Particles accumulate on the filter whenever air passes through, resulting in cleaner air each time. Larger particles are immediately trapped, while smaller ones are trapped later in the process. HEPA filters generally need to be replaced every two to four years; replacement filters are widely available.
HEPA filters are considered the most effective air purifiers for removing particles, as well as the most common and, in most cases, the cheapest. However, they do not remove odors or volatile organic compounds (VOCs), which are emitted from paint, adhesives, and other gas pollutants. One important note: some purifiers advertise as using ‘HEPA-like technology’ or use similar verbiage, but this usually means the filters do not meet official HEPA standards.
Activated carbon: ‘Activated carbon’ (also known as activated charcoal) refers to a form of carbon that has been modified with small, porous openings that expand its surface area. Active carbon technology employs filters that feature low-volume pores that are extremely absorbent and react chemically with some pollutants, sticking to them firmly.
As a result, activated carbon purifiers trap odors, VOCs, and other emissions that cannot be trapped by HEPA filters. However, they are less efficient when it comes to trapping dust mites, microbes, and other pollutants. For this reason, some purifiers feature HEPA and activated carbon filters.
Ionizer: Also known as negative ion purifiers, ionizers rely on active purification (unlike HEPA and activated carbon purifiers that use the passive method). Ionizers essentially zap particles with a chemical charge and collect them using one of two methods:
This method, while scientifically advanced, is somewhat inefficient because it transfers particles to other areas of the room, rather than absorbing them or trapping them in a filter. This poses the risk of the particles breaking free and reentering the air.
Ozone: Ozone purifiers clean the air using ozone gas. This technology is controversial because ozone, when produced at high levels, can be toxic to humans. Long-term exposure to smaller amounts can also lead to health problems. As a result, ozone purifiers have not received official approval from any federal safety oversight agency.
The upside to ozone purifiers is that they are effective at removing odors and some gases — but not dust or other particles. They can also be used to sterilize bacteria and molds — but only in well-ventilated environments. As a result, ozone purifiers often feature ionizers as well.
UV technology: UV technology uses active purification to sterilize mold, bacteria, and viruses, which prevents them from being able to reproduce. However, this technology is not particularly effective at targeting allergens.
The table below summarizes the key differences between HEPA, active carbon, ionizer, ozone, and UV purification technology:
|Type of Purification||Passive||Passive||Active||Active||Active|
|Virus Effectiveness||Yes (99%)||No||Yes||Yes||Yes|
Regardless of the technology used, air purifiers commonly feature the following components:
The following components are associated with certain purification technologies:
Purifiers are considered a sleep aid because airborne contaminants can cause health problems like congestion, headaches, stuffy noses, sneezing, and shortness of breath — all of which are proven to negatively affect sleep quality. This is especially true with people who have allergies, as well as those with asthma.
Additionally, most purifiers produce a subtle whirring sound that similar to the output of white noise machines, which are also used as sleep aids. White noise and other noise colors (such as pink) drown outside noise and allow people to fall asleep more easily. Some air purifiers come with a specialized ‘sleep’ setting, which is usually the lowest and quietest, and thus the most conducive to sleep.
Here are a few important factors to take into account when shopping for a new air purifier and comparing different brands and models:
There are other ways to cleanse the air in your bedroom other than (or in addition to) using a purifier. These include the following: