How Long Does It Take an Air Purifier to Clean a Room?

You just got your air purifier, and you’re excited to put it into good use. After set up, you let it run all day. At this point, you’ll wonder if the air is clean enough and, if not, how long it’ll take the purifier to clean it.

It takes 40 minutes to 3 hours for an air purifier to clear the air of harmful substances. The time it takes to work depends on several factors like the filter and the selected power setting. However, some manufacturers claim to best this time, with their cleaners cleaning the air in 30 minutes.

When considering all the factors in your living area, you can determine how long your air purifier should work. To find out how these factors affect your device, keep reading.

How Fast Does It Take an Air Purifier to Cleanse a Room?

The rate at which a purifier makes the air healthy depends on a few factors. Below are in-depth explanations of the factors that determine air purification speed:

Setting the Power

The power settings control how effective an air purifier will be. You’ll often install your device and set it to the highest. However, turn down the power setting if you want its effectiveness to plummet.

Lower power means that the device will operate at a slower rate. In other words, if the cleaner would typically take 45 minutes to clean the air, it could take 2 hours with a lower setting. 

The Air Purifier’s Cleansing Speed

The rate of air changes per hour, or ACH, is the most critical number to check for when determining how quickly an air purifier cleans the air. It shows how many times the device can clean and circulate the same in an hour. 

The best air purifiers are supposed to circulate the air four to five times in an hour. In other words, it’s supposed to suck back the same portion of cleansed air every 12 or 15 minutes.

The ACH rate of air purifiers that cycle the air just once every 20 minutes is inferior to air purifiers that cycle the air more frequently. This is because these purifiers take in the same air only three times in an hour. 

Avoid using these air purifiers that don’t shift the air out quickly enough. These devices are as good as nothing as they wouldn’t purify the atmosphere enough for it to become healthy. 

Furthermore, consider that the ACH is based on the manufacturer’s tests. Thus, what you see on the package might be different in a real-world environment. This is because it’s affected by other factors in your home, such as smoke.

The Room Size

Cleansing the air varies for different spaces. For instance, it takes longer to purify the air in a large room than in a small bedroom. 

Check for the exchange rate to determine how long it’ll take to clean a large space. To do this, look for a CADR-rated (clean air delivery rate) air purifier. The CADR is a standard test that reveals how many cubic feet a purifier can cleanse per minute. 

The Filters of an Air Purifier

Getting a suitable purifying device isn’t limited to how fast it can cleanse a room in an hour. The filters also have a significant role to play. Without them, a purifier can’t function at all. 

Aside from affecting the cleaning rate, they’re also essential determinants for how well your air will be cleansed. Thus, they’re necessary to help you make the best decision on the purifying device to buy.

The majority of air purifiers may remove pollen and dust. However, it’s essential to be specific about the kind of purifier to buy when it comes to fine particles. 

Fine particles are tiny and invisible to the human eye. Viruses, bacteria, minuscule mold spores, gases, and volatile organic compounds are a few examples.

To deal with these microscopic contaminants, many people use HEPA filters. Beware, not all cleaners with a “Hepa-like” tag use HEPA filters. With this, ensure you get yours from the right distributor.

Pollution of the Atmosphere

The amount of time it takes to clean the air depends on how polluted your space is. If the particles in your room are many, the purifier will take more time to get rid of them. 

For instance, the device will take more time to dissipate thick smoke than a simple foul odor. This is because smoke particles differ in density from bad smell. 

Position of Your Purifier

The air in your room can undergo purification faster depending on where you place the purifier. If the machine is closer to the contaminant’s source, it’ll suck in the air faster than when it’s at a distance.

That said, it’s best to place your purifier closer to a litter box where there’s more stench.

The same goes for keeping food smells out of your kitchen by placing an air purifier close to where you cook. Alternative placement options include setting the air purifier in the middle of the room or a strategic corner. 


The climate condition at a particular time determines how efficient it’ll work. During the cold season, the purifier functions less effectively. Plus, the air is denser at this period, so it’ll take more time to purify.  

On the other hand, the device works better during hot seasons. This is because the air, though hot, is lighter to recycle, making the purifier work faster.

How Do I Make My Air Purifier Cleanse a Room Faster?

An air purifying device can make the air healthy at its own pace. Still, a few procedures can aid it to function more effectively.

Follow any suggestions below to make your air purifying device work faster.

Keep the Windows Closed

Your air purifier can work with your windows open. However, it’s more efficient when they are closed. The reason is that open windows let in more air, allowing more pollutants into your home.

Use Natural Elements

Most times, we underestimate the use of the natural things around us. These elements perform more action than we think. For instance, having houseplants in your home helps recycle air. 

Remember that plants take in carbon monoxide and let out oxygen, perfect for human health. Using this alongside your purifier will make your space a healthy place to be.

Place the Purifying Device in a Strategic Position

You’ll want your device to function to its fullest. This is the only way to get more value for your money.

That said, it’s best to place your device in a corner where there’s a tendency for more smells and pollution. Most times, this is usually beside the waste bin. If you use the type that removes odor, it’ll help to keep your space smelling fresh.

Ensure You Take Preventive Measures

The fact that you have a device that purifies the air doesn’t mean that you should be careless. Therefore, it’ll be best if you try to stay away from things that could pollute your environment. 

Also, always ensure that your space is clean. An air purifier will eliminate bacteria and dust particles from the air, but it won’t clean your floors. Instead, dust your furniture and sweep when you have to.

Maximize the Capabilities of a Hepa Air Purifier 

Air purifiers should run at their peak to clean more air each second of operation. Check and clean your air purifier’s filter regularly to make it more effective. 

Furthermore, make any necessary modifications or replacements to the filters to ensure they operate at their peak.

Keep it away from devices and electronics that could interfere with the wavelength it uses. This will impair its ability to purify the air around it.

How Do I Know When I Need an Air Purifier?

It would help if you got an air purifier when you notice several symptoms. Below are some indications that it’s time to get a purifying device for your home or work area.

Allergic Reactions to Various Substances

Many people experience itchy eyes, a runny nose, and other allergies. Some of these symptoms could result from inhaling unhealthy air. Once you’re exposed to this regularly, you have more allergy reactions.

Getting a purifier might be the best way to control the situation, especially if the allergies are respiratory-related

Constant Asthma Attacks

For individuals who already have an asthmatic problem, polluted air could worsen the case. Something is amiss when you notice that you have frequent attacks. 

Aside from other factors which could trigger the situation, dust and pollen increase attack rates. If you live with this condition and have a pet, there’s a higher chance of more attacks. 

An air purifier can go a long way to curb the attacks by making the air you breathe better for you.

Dusty Furniture

Dust will settle on your furniture even if you’re using an air purifying device. However, the amount of dust you’ll notice with the device is significantly less. So when you have dust settling immediately after wiping your furniture, it’s advisable to get a purifier.

Bad Odors

If the air in your home has a musty or stale stench, you should consider installing an air filtration system. These particles indicate something more dangerous, such as air pollution or an accumulation of deadly bacteria. Staying in such an environment puts you at risk.

Repeated Illness

Many attribute constant sickness to several things. When pinpointing the sickness’s root cause, you should consider your living areas. Ask yourself how safe the air is for breathing.

If you stay in a noisy and busy area, an air purifier should be a compulsory addition to your home. This way, you keep your indoor air clean, reducing the rate of falling ill.

How Long Should You Run an Air Purifier?

It would be best if you turned on your air purifier to its fullest for the first few hours after purchase. Once the device has run for long hours, reduce the power.

Sometimes, you can choose to let your purifier run for 12 hours, maybe more, but never less. However, due to the rate of pollution in some environments, it’s best to have the device running every time. This might reduce its life span, but it’ll do you more good.

How Do I Know If My Air Purifier Is Effective? 

If you’re getting your air purifier for the first time, you’ll be curious to know if they’re working.

Below are three ways to verify that the air purifier is working well:

Check the Airflow of Your Air Purifier

An air purifier’s fan pulls in air from the surrounding area. It recycles the air and blows it out, clean and healthy. If the device doesn’t blow air out, it’s not functioning. 

Furthermore, the fan shouldn’t have to work so hard to bring in and disburse the air. If your air purifier’s fan is too loud, the filter may need to be replaced, or there may be a more serious issue. 

It’s also possible that your air purifier isn’t drawing in enough air to enhance your air quality if it doesn’t make any noise at all. In other words, there should be a slight buzzing but comfortable sound from the device.

Checking Your Air Purifier’s Filters

A faulty filter is one of the most prevalent causes of a non-functional purifier. Sometimes, the damage to the filter occurs after a long time of using the device. Once the air cleaner operates normally, the filter will eventually become blocked and require replacement.

Filter service indicators are available on some purifiers, but it’s always a good idea to double-check. When the prescribed time limit for replacing your filter has elapsed, most of these indicators will sound an alarm to remind you to change them. 

Aside from the alarm, look out for any discoloration on your filter. If the cleaner appears too dirty, it needs replacement.

Filters also don’t last as long in polluted locations, so you’ll have to buy new ones more frequently. You should regularly check your purifier’s filters to know the right time to change them.