How to Choose the Best Air Purifier for Dust
It’s been almost 15 years since I started in the air purifier business. At that time I was thinking about my son and children like him who suffer from asthma. I also could see HEPA filter air purifiers as a good solution for airborne allergies like mold spores or allergens from animal dander.
Allergies remain the number one reason why people buy our air purifiers. The second most popular reason is for the removal of dust from the air.
his was not something I had thought about before but it makes sense since dust mites and dust pollen in the air can trigger asthma and allergy symptoms. There are also neat freaks out there like me who like living in a clean air environment and a room air purifier is a good way to get this fresh air. Plus, I’m lazy and would rather not spend time cleaning.
Getting back to our topic of how to choose an air cleaner for dust removal, it’s important to recognize that dust is airborne particulate matter. The largest sized dust can often be caught in the air filter of your forced-air heating and cooling system. For health reasons (and for lazy people like me) you want to go with a top notch true HEPA air filter to remove the smaller sized dust particles.
You know, the one’s that seem to float in the air the longest. When the sun shines in you can see these dust particles in the air. Makes you wonder how good your indoor air quality really is.
What you may not realize is that the fine dust that causes the most health issues and allergy symptoms are the smallest particles you cannot see. This is a key reason why the HEPA filter is so valuable. It’s the best air filtration technology to properly clean the air.
So, what is the best air purifier for dust?
In practice there is no one answer. Like most things, it really depends. Some of the questions to consider include: why you want an air purifier, how large of a square footage you are looking to clean, is this fine dust, large clumps of dust, pet hair, etc. Keep reading and we will answer all of this and more.
How to Remove Dust from the Air
One of the key technologies in any air purification system is the filters. To do a good job in removing airborne dust particles from the air you will need 2 or 3 types of air filters.
Pre-Filter to Remove Large Sized Dust
The first filter to look for is called a pre-filter. This can be either plain pleated pre-filter or a carbon pre-filter. Both types serve the same function and that is to catch the large dust particles. Large air particles are filtered from the air by the pre-filter so the HEPA filter will last longer and not get clogged with the big stuff. Some examples include pet hair, pet dander, large floating dust or clumps of dust bunnies.
If this carbon pre-filter is made of foam with a sprayed on carbon coating this will provide some odor removal ability. In our experience it works best for light odors.
If you are looking to also remove a challenging odor like the tobacco smoke removal you will not be pleased with the results. There is just not enough activated carbon.
The only exception we have seen is the carbon pre-filters in the EJ and ERIK650A air purifiers. Both of these air purification systems have a few pounds of specially treated activated carbon that is ideal for cigarette smoke removal. This granular activated carbon (GAC) is a key part of the pre-filters for these air purifiers. It gives you not only clean air from the dust removal but also fresh air that smells good.
Anyways, the bottom line is you want a good HEPA air filter. Some are marketed with names include the word HEPA but may or may not meet the HEPA filter standard. The most common is the HEPA-type filter, sometimes called a HEPA-type air purifier.
Some create brand terms like Blueair HepaSilent. I’m not sure if this is a true HEPA filter or not. Another is the IQAir HealthPro where they list their filter as Hyper-HEPA. Based on the specs this is a genuine true HEPA filter.
For Oransi HEPA filtration systems, the Finn, OV200, and Max are Merv 16. The EJ is Merv 17 and the Erik650A is Merv 18. This is important as the higher MERV rated filters can remove more of the smaller dust particles (as measured in microns) that cause issues. This is critical in choosing a room air purifier.
CADR Air Flow
Now that you have a handle on the air purifier filters, we need to explain why you need to move the air through the filters.
Without sufficient air flow you will not see the dust removal you are looking for. This is challenging in any room since there is often air mixing in from other rooms. Or perhaps for forced-air heating system is circulating air throughout the house. Without enough clean air changes in your room, it will not be clean.
One way to measure an air purifier’s ability to move the air through the air purifier filters is the metric called the CADR.
CADR stands for Clean Air Delivery Rate. This is measured in cfm or cubic feet per minute. It’s like a cfm air flow number
Where it gets confusing is in determining how this number relates to the sq ft size of your room.
Obviously, if your room is sized 15 ft by 20 ft it is 300 sq ft. But the CADR rating is in cubi c feet per minute and not square feet per minute. So, to convert the room size to cubic feet multiple the sq ft number by the ceiling height. This will often be 8 or 10.
To keep the math simple, let’s use 10. Your 300 square foot room with 10 foot ceilings has 3,000 cubic feet to clean.
If the air purifier can deliver 300 cfm (CADR) then it will take 10 minutes to clean the air in the room once. At this rate it will filter the air 6 times per hour.
Click on this link to learn more about air purifier room size and square footage co verage.
We see some brands promote one air change per hour up to five air changes per hour. To get the air cleaning you desire you will get better results with a higher CADR rating.
Now that you’re a CADR ratings wizard, I have to point out that CADR is measured at the air purifier’s highest fan speed setting.
So, while the air cleaner may provide the air circulation you are looking for, you also need to consider the noise level.
For full disclosure, Oransi is a member of AHAM. AHAM is the Association of Home Appliance Manufacturers. This group sets the air purifier standards for the US. They developed the CADR ratings system.
While the CADR is good in providing a way to compare air flows, it’s not a perfect system.
For example, it does not consider the noise level on the highest fan speed. If you are not going to run the air purifier at this level then the CADR is not so meaningful.
So, getting back to noise level there are a couple other points to make.
As a user of our air cleaners, we know how important it is for your air filtration system to be quiet. It’s an engineering challenge since true HEPA filters and activated carbon filters add a lot of air flow resistance. This means sound.
Noise level is measured in decibels. What you may not know is that the sound level is represented on a logarithmic scale. What this means is that for every 10 dB increase the sound level doubles. So a 70 dB noise level is twice as loud as 60 dB.
To overcome this, we make our air filters larger. It’s like drinking through a larger straw. This way you can have higher efficiency filters to remove airborne allergens without sacrifici ng air flow or adding a lot of noise.
Other Air Cleaning Technologies
What we have listed above is the best way to remove airborne dust particles from the air. There are some other technologies used in air purification units.
The purpose of this section is to highlight them. Though as it relates to helping with your dust mite allergy or less dust to improve indoor air quality, these offer little to no benefit.
UV-C light can be effective in preventing growth of all types of household mold . Especially if you have a strong ultraviolet light in your forced-air heating system. But if what you are looking for is to kill dust mites or breathe better with less dust in the air, then a UV-C germicidal lamp will not do it.
This is because UV lamps are not able to capture airborne dust particles. It simply shines a powerful light that keeps things like mold and mildew from growing. If you suffer from allergies and asthma from mold then an air purifier with UV light may be a good option.
For mold removal see the best air purifiers for mold. In addition, here are our best air purifiers for allergies if you need something more specific.
Plasma technology is a more recent innovation in the world of air purification. The two most popular are plasmawave technology and plasmacluster technology.
My understanding is these are marketing terms for the use of positive and negative ions. This is somewhat similar to an ionic air purifier where electrical charges are used to make it easier to catch the HEPA filter.
Since this is a newer technology, there is some concern around ozone being produced as a by-product. In a sense a secondary pollution. You have the potential for ozone generation any time you emit electrical charges.
As it relates to the removal of dust, this technology can provide some benefits. Our approach is different. We feel if you use super high quality filters, you don’t need to use electrostatic technology to remove airborne allergens. As allergy and asthma sufferers ourselves, it’s not worth it to create an indoor air pollutant.
In summary, we set out to address what you need to know to choose the best air purifier for dust removal in your home or office.
When we say dust, we mean fine dust, dust pollen, dust mite allergy, or any other airborne particle that could trigger your allergies or make you feel not good since you have dust in the air.
The first step is to ensure you have the best filters. A true HEPA filter will remove the most and smallest airborne allergens. Other filters like HEPA-type air filters remove a lower efficiency. These can be good for use in your HVAC system if you want to remove the large dust. But, if you want to remove the fine dust particles you need to go with a genuine true HEPA filter.
If you need odor removal, whether from cigarette smoke, volatile organic compounds or any other source then you will also want an activated carbon filter. Here are the best air purifiers for smoke removal .
While the best filters are a good start, you also need to have a strong fan to get enough air flow. Otherwise there will not be enough air circulation. A good way to compare the air flow of air purifiers is with the CADR ratings scale.
Another consideration is noise level. If you are using the air filtration system in your bedroom, you most likely is want the air purifier to be quiet. You can get true HEPA filters and a strong air flow that is quiet. That’s what we do with Oransi air purifiers by making our filters larger. And we use high quality motors.