How do air purifiers work?

Even though different air purifiers will zero in on different particles in the air, most will have a similar working mechanism. For the most part, all air purifiers use a system of internal fans to pull indoor air and run it through very fine sieves, or filters that sift particles from the circulating air. As air flows into the machine, the filter traps any particles present. So the finer the filter, the more particles it traps.

Air purifiers work

The accepted benchmark for air filters that has been set by HEPA or the High Efficiency Particulate Air is guaranteed to trap 99.97% of airborne particles larger than 0.3 microns.

The purifier then circulates the cleaned air back into the indoor space and the process reruns over multiple times to keep your environment healthy.

Features to consider while choosing an air purifier

As you go looking for an air purifier, you’ll notice that these machines come with a variety of functions, upgrades, and options. To make sure that you get the one to fit your needs best, consider the following features:

Number and type of filters

The number of filters you’ll find on an air purifier will vary from one model to the next. Most models will range between two and four filters. However, most basic models will only start off with one filter such as the Hamilton Beach 04386A, while the more advanced ones can go up to five such as the VEVA 8000 Elite Pro Series and the Partu Air Purifier. We have a range of these on our list here to give you a complete choice in what you’re looking for.

As far as types of filters go, there are a few different choices available. Each type uses a different technology and targets different pollutants.

HEPA filters Typically more expensive than other kinds, HEPA-certified air purifiers are considered one of the most effective. They contain a mechanical filter using HEPA technology and are highly capable of trapping particulate pollutants. Any of the best air purifiers for smoke odor will have one HEPA filter installed along with a combination of other types for optimal performance. All the models that we have gathered here today include a HEPA filter paired with others to give you a smoke-free indoor environment.

HEPA filter

The filter itself can be made of any material as long as it meets the HEPA standard of trapping 99.97% of pollutants 0.3 microns or larger. These filters are highly efficient, trapping particles and don’t dispense them again into air. While they do remove visible smoke, they don’t really eliminate odors or fumes and need help from other types of filters.

Activated carbon filters – These filters use activated carbon in a specific form. It has innumerable tiny pores which are absorbent and provide an extended surface for trapping gases, fumes, and odors. Activated carbon is extremely porous and yields numerous nooks and crannies to trap passing molecules. The larger particles simply get stuck in the pores while the smaller ones get trapped.

These filters work best in places where the odor is an issue. They help make the indoors smell clean and fresh removing cooking smells, smoke and pet odors.

They are also cheap as compared to other types but are only effective for removing odors, smells and fumes and not anything else. That is why these filters are always paired up with other types to be more effective.

Activated carbon filter

Ionizing filters – This type of filter doesn’t essentially purify the indoor air per say. Instead, these purifiers emit negative ions into the surrounding air which then attach to positively charged airborne particles. When the two combine together they become too weighty to stay airborne and settle on other surfaces. So while they may be extracted from the surrounding air in a sense, they are still present within the room. If you’re looking for an ionizing filter with an electrostatic plate, then take a closer look at the hOmeLabs model we have discussed today.

UV filters – This technology is different from the ones mentioned so far. UV filters use invisible light to attack pollutants rather than have them pass through an actual filter. It remains inside the air purifying unit and isn’t emitted into the surrounding room. The light used in this mechanism is UV-C band which is safe and does not present any concerns. Its primary function is to destroy viruses and bacteria that are airborne.

CADR level

When you’re looking to get the best air purifier for cigarette smell, or any other similar odor, you may come across a rating saying CADR. This stands for Clear Air Delivery Rate and indicates how thoroughly an air purifier can clean a particular sized room.

The higher the numbers, the more efficient the filtering mechanism is at getting rid of the contaminants. You can use the CADR rating to compare two different air purifier models to see which one will work better for you. Models that give identical square footage coverage and come with CADR ratings will tell you which air purifier will work better for removing specific pollutants.

Coverage area

Air Purifier in the center of the room

Most air purifiers are rated with a coverage area and you should get a unit suitable for a particular room you’re intending to use it in.

Your device should have square footage measurements that either equate or are greater than the size of the intended room.

Along with square footage placement of the unit is also essential to achieve the best results. Most units work best placed in the center of the room. If you put it in one corner of the room, it will only take longer for the air purifier to do its job. This is true for ionic filters as these models emit ions in a 360-degree circle and need clearance all around to work correctly.

Air purifiers that use a HEPA or carbon filter can be placed two-three feet away from a wall or furniture which gives them enough surrounding airspace to work at maximum power.

Noise level

Noise can be an essential factor when it comes to buying an air purifier. Ideally, the unit should run on the lowest setting if it fits the square footage for the area correctly. If you find that you need to put it on higher settings, then you may have a unit too small for the area. It also means that the noise level will rise when the purifier runs on the maximum mode.

Noise also factors in when you use the air purifier in a room where you sleep or work. For the sake of efficiency, we recommend using a larger model and running it on a lower speed instead of cranking up a small one on high speed.

For models that use a HEPA or carbon filter, there is always a fan mechanism. The fan is what draws the air into the purifier and pushes it through the filters. And fans make noise.


Air purifiers come in a vast array of dimensions with some of the smallest being only slightly above 6 x 6 x 7 inches such as the hOmeLabs Ionic 3 in 1 air purifier. A smaller, compact unit will work well for compact spaces as long as it is sized correctly.

8 Awesome Air Purifiers to Get Rid of Cigarette and Wildfire Smoke

So while you may wish to consider the actual size of the unit, you still need to refer to the coverage it can provide regarding square footage. That remains a priority regarding effectiveness of an air purifier.

Extra features

Along with standard features, air purifiers also come outfitted with extra characteristics to add to their performance. These can include digital controls to allow for more precise settings, indicators for filter replacement, and programmable timers that automatically shut the device off after a certain time interval. Some models come with a handle for easy portability or casters to roll bulkier air purifiers from one room to the next. Others also will feature a night light which can be convenient to light a darkened room or suitable for use in the bedroom.

Why do you need to get rid of cigarette and wildfire smoke?

The hazards of cigarette smoke, either directly or as second-hand smoke are well known. But inhaling wildfire smoke particles can have equally detrimental effects. Both types of smoke can leave your lungs taxed and exhausted as these are your body’s primary filters. Extended exposure can bring about chest pains, rapid heartbeat, wheezing or an asthma attack. To clear the air, you need to invest in a quality air purifier so that your indoor air gets cleared of pollutants and minimize any potential health threats.