As air purifiers have increasingly become more and more popular with consumers, there has been an outpouring of pertinent information for consumers on the competing air purification technologies. One of the major technologies used in many air purifiers today is called HEPA filtration or a HEPA filter. A HEPA (High-Efficiency Particulate Air) is an integral component to air purifier systems that promise to improve the overall indoor air quality. However, as these HEPA air purifier have become more prominent inside a vast number of air purifiers, criticism has begun to circulate about this air purification technology.
We are going to take a look at what the High Efficiency Particulate Air standard means and how this technology can deal with various types of pollutants within your home, in comparison to other competing air purification technologies.
What is a HEPA Filter?
If you are shopping for an air purifier, the chances are you have likely heard of a HEPA filter along your searching and research. HEPA, an acronym that stands for High Efficiency Particulate Air, is an important and popular form of air purification technology that is able to offer a highly effective technology for particulate removal. These contain regulated standards that must be met in order to comply with HEPA.
The High Efficiency Particulate Air standard was structured and implemented by the U.S. Department of Energy, as the first HEPA filtration was developed in the 1940s for use in facilities that contained nuclear materials. These filters were able to keep potentially radioactive particles contained, as the HEPA was able to shield and contain radiation including particles of dust and moisture that become irradiated.
Since the use of HEPAs in facilities with nuclear materials, it has been used in numerous industries and applications, even breaking into the consumer market for HVAC units, vacuum cleaners, and indoor air purifiers.
HEPA vs True HEPA
The more and more popular HEPA filters become, the more people try to use variations of the trendy HEPA. Some air filters are labeled ‘HEPA-like’ or ‘HEPA-style’, these terms although they sound comparable to a HEPA, are not HEPA standard. Another misleading term used in the market today is ‘True HEPA’, these are filters that have not met the standard of HEPA.
The HEPA specification is based on certain criteria such as the size of the particles and how many of them pass through the designated HEPA filter. To meet the standard for a HEPA, it must meet particulate removal of particles as small as 0.3 microns in size, with a 99.97% efficiency. This means that if you send ten thousand 0.3 micrometer particles through a HEPA filter, only three particles would pass through the HEPA.
Another specification of HEPA standard is the tight construction of the filter – which must be airtight. If air flow can get around the filter, then the filter is inept and is not qualified as a HEPA. This is the major flaw for those filters labeled ‘True HEPA, and thus it will require a more precise manufacturing to create a HEPA standard that includes particulate removal as small as 0.3 microns in size, with a 99.97% efficiency, and an airtight constructed filter.
How Does This Technology Work
To understand exactly how a HEPA works, think of it as a mesh of intricately tangled fibers that act as a barrier or shield. The shield contains a weaved material like that of a strainer, with small holes to capture large particles like dust, dirt, hairs, and other airborne debris.
The outer layer of the HEPA works as a basic filter, as it filters to prevent the bigger dust particles from passing through the air. The inner layer, conversely, does not work the same as the outer layer, instead it traps the particles in different techniques. The heavier particles will move slowly and gradually sticking to the fiberglass inside the HEPA. The lighter-weight particles travel faster and either have a collision straight with the HEPA fibers, or they are able to pass thought the material.
According to HEPA standard, however, the possibility of particles passing through that are larger than 0.3 microns are rare, as the HEPA has a 99.97% efficiency for particulate capture and removal.
High Efficiency Particulate Air Filter Material
HEPA filters are made of a very fine glass thread that has a diameter less than 1 micron in size. The fine glass threads of the HEPA are tangled together and compressed to form a filter mat media. The individual threads are so tiny and microscopic that a big portion of the media mat consists of air. The openings inside the mat are small, generally smaller than 0.5 microns, allowing the HEPA to collect particles down to 0.3 microns in size.
How Long Does a HEPA Last?
The life of your HEPA air filter will depend on a variety of factors including the size of the filter, the usage of the filter, and the amount of space the filter is treating within your environment. Most HEPAs, under the right conditions, will last a consumer for close to 2 to 3 years. This is much more manageable in comparison to other competing air purifier technologies, such as carbon. Carbon filters fill by weight, so the more pollutants inside your environment, the more frequent you will need to change out the filter. These carbon filters, in comparison to HEPAs, may need to be changed every month, or even worse a couple times a month if conditions are severe in the environment.
Pros of High Efficiency Particulate Air Filtration
The HEPA technology has many advantageous benefits that it provides to consumers looking for an air purifier. In comparison to other competing air purification technologies, the Pros of HEPA is extensive. Below we are going to list the benefits of this type of filtration:
- No Byproducts Produced or Emitted: Air purification technologies such as ionizers, ozone, and PECO all produce and emit a hazardous byproduct into the air when they are utilized in an environment. HEPA, however, has the advantage of not producing any byproducts or ozone like competitors.
- Effective Particulate Removal: As we have discussed, HEPA filtration will capture particulate matter as small as 0.3 microns in size, with a 99.97% effectiveness.
- Ideal for Allergy Sufferers: HEPA filters contain the ability to remove most airborne particles from your home that may contribute to your adverse allergy reactions. For those individuals that suffer from allergies, that have utilized a HEPA filtration, they have seen improvement in allergy conditions due to the removal of allergens from the air.
- Long Filter Life: The life of a HEPA, as we stated up above, usually lasts for about 2 to 3 years. In comparison to other competitors, such as Carbon, these filters last for a lot longer. This means you have less cost associated with maintaining your HEPA air purifier.
Cons of This Air Filtration
When it comes to the shortcomings of HEPA filtration, there are a few that can worry buyers before they purchase. The two cons associated with HEPA filtration include the following:
- Small Pollutants Can Escape Filter: Although HEPA filters capture and remove particulates larger than 0.3 microns, there is a potential for smaller particles to pass through the filter that can be hazardous when present in your air. These smaller particulates can cause an array of potential health issues if inhalation or ingestion occurs. Even though this is a downfall for HEPA, the potential for particles smaller than 0.3 microns in your environment is unlikely, and other competing technologies will also be inept in removing these ultra-fine particulates.
- Mold & Bacteria Growth on Filter: When mold and bacteria accumulate inside the air system on the HEPA filter, these organisms have the potential to grow within the filter. They are microorganisms and when they become collected, they can multiply and become released back into the air. If mold and bacteria are an issue within your personal indoor environment, it is important to look for a HEPA air purifier that utilizes a combination of UVC lights to provide a high efficiency of kill to collected microorganisms on the HEPA filter.
Conclusion: HEPA Technology
The HEPA technology is a highly effective and advantageous method for air purifiers. HEPA is good at removing larger particulate matter like pet dander, pollen, and dust mites. If you are looking for a technology that is effective at particulate removal, without emitting byproducts or other dangerous chemicals into the air than the HEPA technology is your best bet. Keeping your air clean and free of particulates and dangerous chemical byproducts.