What is the HEPA Filter in your Air Purifier?

What is the HEPA Filter in your Air Purifier and what does it do? This is probably what you are wondering. Well to know what a HEPA filter does it is important that we rethink our definition of pollution.

Upon hearing the word pollution and pollutants people tend to think of multi-billion dollar industries dumping tonnes of waste into water bodies or landfills. While that holds true, pollution exists much closer. In fact, the Environmental Protection Agency says the biggest air pollution problems exist indoors. Pollutants that exist indoors range from excessive moisture, volatile organic compounds, pesticides, dust particles, viruses & bacteria, and radon.

Related: Best Air Purifier in Dubai

This can irritate your lungs and contribute towards the development of allergies and asthma. Radon, however, is a dangerous byproduct and has serious health implications. Simply cleaning your home with a vacuum cleaner, phenyl, and mop doesn’t quite cut it, as the pollutants are in the air and not just on surfaces.

A HEPA air purifier is worth investing in as it filters out the air removing any particles floating about its vicinity. HEPA stands for “high-efficiency particulate air”. It works by forcing air through an uber fine mesh that traps harmful particles such as pollen, pet dander, dust, tobacco, smoke, and dust.

HEPA filters usually use three different mechanisms to trap dust particles as it passes through the airstream. Some get trapped into the filter by flying straight into it while others get caught as they brush past. At lower speeds, particles move about freely through the filter, known as Brownian motion.

Types of HEPA filters

A true HEPA filter traps up to 99.97 percent of dust particles that are 0.3 microns in diameter. If you’re having a hard time picturing it a typical human hair is roughly 50–150 microns in diameter. A HEPA filter is traps dust several hundred times thinner than that. You also get HEPA-like and HEPA-style filters. But they do not meet the strict standards and are portrayed in a similar light for marketing purposes. Such filters do little in terms of stopping mold spores and even some bacteria and viruses. They are not as finely made and only share the intricate design structure which defeats the purpose. A genuine HEPA filter proves more hygienic as it stops mold spores from spreading. Some HEPA filters even stop bacteria from polluting the air. A very important differentiating point between a true HEPA filter and its counter part is the fact that in a real HEPA filter the construction of the filter case must be airtight. If the air flow is able to get around the filter then the essence of the filter is lost. In short, it cleans the air around you on a microscopic level.

How much space does a HEPA filter clean?

Air purifiers that use HEPA filters require an increased suction power, thus, consuming more power. Often reflected in its increased price. It is important to note that HEPA filters come in a variety of sizes and shapes. They perform different functions and thus also cover various area sizes. They can cover areas anywhere from 50 square feet to 1,000 square feet and provide contamination-free air. Remember, a HEPA filter removes 99.7% of particles 0.3 microns or larger.

How do HEPA filters help?

HEPA filters rid the air of impurities giving you cleaner and fresher air to breathe. In doing so, remove a number of airborne particles that cause or aggravate allergies. If you have vegetation outside your window then pollen is one contaminant your air purifier will take care of. If you have pets at home, keeping them outdoors isn’t viable due to the harsh conditions, instead, an air purifier can help keep your area clean. In conjunction, use a vacuum cleaner with a HEPA filter for areas such as coches, beds, rugs and ensure there is little-to-no fur lingering. This will limit the number of pollutants in your home. It is important as not all particles remain in the air. They settle into the tapestry, bedding, carpets, and other areas of your home.

Air purifiers also help reduce the presence of harmful gases in your home. This includes carbon monoxide, sulfur dioxide, nitrogen dioxide. In large quantities, these gases can be fatal. Further, if you have recently painted your home or cleaned dusty areas the number of pollutants are greater. Paint, varnish, cleaning products, and pressed wood furniture leave both residue and airborne particles capable of causing irritation. It serves well to remember that a HEPA filter with an activated carbon or charcoal filter helps eliminate odors. Meaning even if you cook foods with strong smells in your household they are quickly taken care of.

How to clean the HEPA filter?

If you have a regular filter after the usage you will need to replace it. Some allow you to buy and replace them with HEPA filters. Conversely, you can also buy one with a washable filter that needs to be changed every 6 months. Changing the air filter every 6 months ensures you leave no room for dirt. It also means that in case your filter withstands damage it is quickly replaced and doesn’t compromise the quality of air. However, if you buy an air purifier with a permanent mesh HEPA filter then you can use a soft microfibre cloth for dusting it.

What are the limitations of a HEPA filter?

HEPA filters are great at reducing the number of contaminants and particles in the air. However, they do very little when it comes to ridding the area from smells and odors. That being said, many air purifiers come with combinations of filters that address the issue. With a carbon activated or charcoal filter, your room is rid of unpleasant smells.

Next, in an air purifier the HEPA filter isn’t capable of removing the pollutants trapped in rugs, drapes, or other furniture. For this it is advisable that you dust and vacuum your home regularly. Regions with higher moisture levels and elevated temperatures experience mold growth as well as bacteria growth, which can even occur on the HEPA filter. So cleaning or replacing your HEPA filter is of utmost importance to ensure you do not introduce more pollutants into your home.

Lastly, Volatile organic compounds (VOCs) cause a number of issues such as headaches, skin reactions, eye, and respiratory tract infections. VOC inhalation over prolonged periods links to cancer and other harmful illnesses. Formaldehyde is the most common one, which is responsible for many serious health issues each year. Sadly, VOCs and viruses are too small for the HEPA filter to remove.

Before you buy

Prior to purchasing an air purifier with a HEPA filter ensure you know exactly why you are buying it. If the reason is to reduce irritation and allergies then a HEPA filter makes sense. Ensure that is a proper HEPA filter and you shall reduce over 90% of the pollutants. If you simply want an air purifier to eliminate odors then a carbon or charcoal-activated filter should be your first preference. Remember, HEPA filters are more expensive to run and have increasingly powerful motors which makes them noisier than other filters.

Danesh Engineer
Leave a Reply