What is a HEPA Air Purifier

Winix WAC9500 True HEPA Air Cleaner with PlasmaWave Technology

HEPA Air Purifier: What it is and How it Works

One of the most popular appliances in the market is the HEPA air purifier. Most households have this air purifier to address their allergy needs. It can remove airborne allergies like dust, pet dander, pollen, mold spores, dust mites that can trigger allergic reactions to highly sensitive people. More importantly, the common household pollutants and equally dangerous are the smoke particles and volatile organic compounds commonly known as VOCs could also be removed by the air purifier.

Indeed! It works just like magic! Imagine air free from all these pollutants. You won’t have to worry about any respiratory allergies or cleaning the room every now and then. What’s better with these air purifier true HEPA filter units is that it can already capture bacteria and other microorganisms in the air thus reducing their concentration which can be damaging to your health.

So, if you’re planning to purchase one today or in the coming days to come, first know what a HEPA Air Purifier is. This is an in-depth explanation of what it is made of and how it does the air purifying. You should also know what the benefits are to help you decide on which is the best HEPA air purifier to buy!

What does HEPA mean?

Most of the best selling air purifiers online are the HEPA air purifiers. We commonly see the term “HEPA” tagged along with the model name of different brands. HEPA stands for High-Efficiency Particulate Air. It is a type of air filter used in several systems that need a clean air like those in the vehicles, home filters, hospitals, and airplanes. It is not merely put in a unit’s name; it is a qualifying status for the product. The filter to be labeled as HEPA, it has to pass certain standards set by the Department of Energy.

How does a unit qualify as a HEPA air purifier?

Indeed, buying a HEPA air purifier is not just a small deal because for a filter unit to have a HEPA label it should pass government standards. A filter must be able to remove 99.97% of all particles from 0.3 micrometers up. However, being Hepa qualified does not necessarily mean highest standards, it’s just one of the classifications of air purifiers. These will be further sorted according to its filter capacity.

How small is a 0.3 micrometer?

A micrometer or commonly known as a micron is very small! It is equal to 1 millionth of a meter. Particles this small cannot be seen by the naked eye. This is very important to point out for HEPA filters because most allergens are in this size. They are very difficult to capture or filter and if pass through the respiratory system may cause coughing, sneezing, and runny nose.

These are the common air contaminants we can see in the house along with their sizes. Human hair (70-100 microns), pet dander (0.5-100 microns), Pollen (5-100 microns), Mold (2-20 microns), Plant Spores (6-100 microns), smoke (0.01-1 micron), dust mites (0.05-50 microns), bacteria (0.35-10 microns).

How does it work?

HEPA Air purifier How it works

HEPA filters are made of a mat of randomly arranged fibers. These are commonly made of fiberglass the size of 0.5 to 2.0 micrometers. The important detail is the distance between one fiber to another. Particles are trapped in the mat of fibers through the following simple processes.

Interception: Particles usually follow a single pathway by an air stream produced by your air purifier.

Impaction: As the air stream continues to flow in and out of the machine, larger particles are unable to surpass fibers; therefore they are attached to one of the fibers. This is commonly coined as capturing the particles by forcing them into sticking into the fibers.

Diffusion: Molecules in the air collide with smaller gas molecules therefore, their motions are stopped.

Can HEPA air purifiers really kill viruses and bacteria?

HEPA Filters cannot only capture inanimate objects but living microorganisms as well. Once they are captured, these bacteria and viruses may die. The HEPA filter is a dry environment and is not an ideal moist medium for bacterial growth. Yes, these microorganisms can be killed. However, if the air coming into the filter is moist, bacteria can grow.


Indeed HEPA air purifiers can do well in cleaning the air from common household allergens. Now, let’s see the benefits of having a HEPA air purifier at home.

If you are exposed to air pollution, this may cause several health issues like allergies and respiratory infections. Little did we know that air inside our house is equally polluted as there on the outside. Breathing air with many pollutants can cause aggravation of present conditions. Respiratory or not, inflammation can happen because of these particles. You should have an air purifier if you have one of these persons:

  • If you’re concerned about having the healthiest home possible.
  • If you want a pet but is afraid of the allergies pet dander may cause.
  • If you already have asthma and allergies with many recurrent attacks.
  • If you want to remove smoke odors and other common household odors that have long been lurking in your homes.
  • Found yourself in any of these situations? You should really think of buying one.


However, there are some customer concerns about having a HEPA air purifier. Some of the machines have gaseous by-products that can be hazardous to your health. In addition, most customers are complaining about the level of noise, the frequency and expense of changing the filters, electrical energy consumption and visual appeal.

In order for you to resolve these possible concerns, you can read well customer reviews regarding the product you will buy. You can also call the customer service of the company to know the noise level (in decibels) for example to prepare you for what to expect in a product. With regards to the frequency of replacement, there are several HEPA filter purifiers which can last 3-5 years, some are even permanent. What’s important is that you clean your units regularly.

TOP 5 Best HEPA air purifiers 2017

The Haverhill HAP52010E is one of the best HEPA air purifiers. It covers spaces up to 538 square feet. And it has many features for example 6 fan speeds, air quality indicator, automatic mode, night mode, filter check indicator, carrying handle, and even smoke and odor removal modes. Ideal for allergy and asthma sufferers and those with light chemical sensitivities. Another great choice is Whirlpool 510 (AP51030K) Whispure.

The Germ Guardian AC4825 3 in 1 True HEPA air purifier with UV Sanitizer and odor reduction is not only the number one best seller but also quietest bedroom air purifier. This air purifier is one of the best in the price range under $100. The Germ Guardian AC4825 Air Cleaner is ideal for small to medium spaces and has a recommended room size of 155 square feet (14m2).

Coway AP-1512 Air Purifier is beautiful with a unique design. This compact air purifier holds high-quality filtration, awesome features – air quality sensor, filter replace indicator, auto mode, timer, and enough to purify large spaces up to 326 square feet. On lowest setting uses only 7W power.

The Winix WAC5500 is a great air cleaner for rooms up to 350 square feet (32.5m2). Best price for such size space. The Winix WAC5500 contains a 99.97% efficient True-HEPA Filter, Odor Control Carbon Pre-Filters, and PlasmaWave Technology.

Rabbit Air Minus A2 SPA780A is one of my favorites, it is powerful, really impressive purification, great quality. Many features – odor sensor, air quality indicator, auto mode, remote control, light sensing, mood light etc. Can be mounted on the wall, customizable designer panels, 5 fan speeds. Energy star qualified. This air purifier includes everything you need.

What else should you know?

Please share this post if you liked it. Also, read more info about air purifiers and air quality on my blog here. Feel free to read all resources on my webpage. You will find air purifier comparison charts, air purifier buying guide, reviews and a lot more.

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My name is Ryan. I have had a hard time dealing with my allergies. Happily, I found that an air purifier was effective to ease my allergy symptoms. I spent a lot of time researching the best air purifier. I know how hard it can be to find the suitable one.

During the reading period, I also read a lot about humidifiers and dehumidifiers. I learned the mechanisms behind the technologies as well as the manufacturers and organizations within the industry.

I now feel convinced that I have built a guide that shows you all you need to know about air purifiers, humidifiers, and dehumidifiers. So I came up with the idea of creating this website.

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