With increasing air pollution, allergy-inducing pollen, and harmful bacteria, air purifiers are a great way to keep the air in your home and your lungs healthy. But one thing that’s often debated over is whether they double as peaceful sound machines or are just another noisy appliance.
An air purifier’s noise level depends on the size, type, quality, and brand. Larger air purifiers are usually louder but more powerful, while smaller ones are quieter and used for smaller spaces. Built-in HVAC air purifiers are virtually silent, producing the least amount of sound.
There are many different factors to attribute to how loud an air purifier is, and the article below explains what those factors are.
Should You Get an Air Purifier?
Honestly, that’s a question only you can answer. People who choose to buy one might have severe allergies, live in an area with poor air quality and/or high pollution rates, or need to get rid of harmful gasses and foul odors, and there’s plenty of air purifiers that promise to fix one or all of these problems.
Many professionals use air purifiers either for industrial work, painting, and other fields. For whatever reason you want one, it would be best if you were mindful of what exactly an air purifier promises to do and how loudly it’s going to do it.
How Loud Is Too Loud?
Many people with air purifiers enjoy the clear, ambient sound similar to white noise. Some say it helps them get to sleep in the same way sound machines can. But some people think the noise can be an inconvenience when they’re watching tv or just need some peace and quiet.
Sound itself is measured in decibels or dBA. There’s a lot of math and science that goes into what we consider sound. I’ll spare you the details, but if you’re interested, Britannica has a wonderful article about it. We’ll focus on the decibel scale section.
Our ears are nonlinear; in layman’s terms, that means that we can process quieter sounds better than loud ones. For example, most people tolerate or even enjoy the crunching sound that leaves make when you step on them but have an aversion to a balloon popping or a lawnmower revving.
There are scales listing off various sounds and their decibel levels. There’s a ton of variation and a much more detailed list, but here are some general examples:
- 0 decibels is complete silence, which exists virtually nowhere in nature.
- Twenty decibels is a television or a library.
- Fifty decibels is a restaurant.
- Eighty decibels is a vacuum cleaner.
- One hundred decibels is a blow dryer or chainsaw.
- One hundred thirty decibels is gunfire.
- One hundred eighty decibels is a rocket launch.
Coming back to air purifiers, they can sit as low as 15 dBA and as high as 75 dBA. That’s a pretty big difference. From what I gathered, the bigger and/or cheaper it is, the louder it will be. Of course, that doesn’t mean it doesn’t clean and deodorizes the air. It just means it does so very loudly.
The huge ones are usually used in an industrial setting. Most air purifiers will advertise being specifically for bedrooms, nurseries, or living rooms. Many manufacturers list the decibel level, so you know how loud it’s going to be.
Types of Air Purifier Filters
There are different types of filters for various problems, so some purifiers focus on eliminating just one, and some have multiple filters to take care of everything at once. These are the most popular types of filters used.
Probably the most popular type of filter, HEPA (High-Efficiency Particulate Air) filters remove 99.97% of particulates, including bacteria, mold, and pollen. They specifically advertise that they can catch particles that are 0.3 microns because, according to the US Environmental Protection Agency, 0.3 microns is generally the most challenging particle to capture.
The science behind this is confusing, as you’d think anything smaller than 0.3 microns would get through easier, but no, HEPA filters catch particles bigger or smaller more efficiently. Again, I know that doesn’t make any sense, but HEPA proves that not all things have to make sense. It just has to work.
Activated Carbon Filters
This filter is used to remove unpleasant odors or harmful gases. Activated carbon is made by taking wood, bamboo, coconut shells, or other naturally combustible materials and burning them in a vacuum chamber, leaving only the charred substance usually referred to as natural charcoal. Different materials are used for different types of charcoal.
It is then ‘activated’ either physically by exposing it to oxygen or steam at very high temperatures or chemically by submerging in a solution. Phosphoric acid and sodium hydroxide are some of the many chemicals used. Both processes help charcoal absorb VOCs (Volatile Organic Compounds) like tobacco smoke, paint fumes, and other harmful gasses.
Activated carbon filters don’t trap harmful particles, so it is usually paired with a HEPA filter or something similar. There are air purifiers with only activated carbon filters, but there are plenty with both filters around the same price.
Your HVAC (Heating Ventilation Air Conditioning) unit can be one of the primary indoor pollution sources in your home because the air ducts can be full of dust or mold. HVAC filters claim to be virtually silent and last longer without maintenance but are also the most expensive. You’ll need a professional to install it for you, as it can be dangerous to do it yourself.
Popular Air Filters
Because there are so many o different air purifiers to choose from, there’s plenty of other lists online with a lot of great information, like this one from Clean Home Zone. Below I will compare some of the ones that came up first on Amazon.
Even at its relatively high price, this air purifier is on the cheaper end of the spectrum. Although it’s advertised for smaller areas like bedrooms or nurseries, it’s 15dBA levels higher than the recommended maximum.
- Filter Type: HEPA
- Room Size: Max. 200 sq. ft. (18.6 sq. m.)
- Decibel Level: 55dBA
This air purifier has multiple filters for cleaning and deodorizing the air, along with different speeds and an LED display.
- Filter Type: Preliminary filter, HEPA, Activated Carbon
- Room Size: Max 500 sq. ft. (46.5 sq. m.)
- Decibel Level: 23dBA
This one claims to have a 5-in-1 filter system and an air quality sensor that tells you how clean your air is.
- Filter Type: Cold-Catylist, Activated Carbon, Antibacterial, HEPA, Ionizer
- Room Size: Max 350 sq. ft. (32.5 sq. m.)
- Decibel Level: 20 dBA
Like most HVAC air purifiers, this HVAC Electronic Air Purifier is expensive and needs to be professionally installed. It is the quietest and does not need much maintenance.
- Filter Type: HEPA
- Room Size: Whole House
- Decibel Level: N/A (most HVACs are virtually silent)
In short, there are many types of air purifiers with different noise levels. Larger or cheaper ones are generally the loudest. Air purifiers over 40dBA aren’t recommended for bedrooms. 25-30 dBA are great for people who like white noise. 15-20dBA is best for people who need it as quiet as possible.
HEPA filters remove 99.97% of harmful particles like bacteria, mold, dust, pollen, and more. Activated carbon filters remove VOCs, dangerous gasses, and bad odors like paint fumes. HVAC filters are installed into your air ducts by a professional; they are virtually silent and the most expensive.