What is a HEPA Filter and What Does it Do?

What is a HEPA Filter and What Does it Do? Related Information:

A HEPA filter is used in an air purifier to help filter harmful pollutants and allergens out of the air you breathe. This technology was developed by the U.S. Atomic Energy Commission to remove the airborne radioactive particles from the air. In order for a filter to be considered a true HEPA, it has to be able to remove 99.7% of the particles as small as 0.3 microns from the air. HEPA is an acronym for High Efficiency Particulate Air and the filter works by circulating the air to purify it.

The air in homes and building is polluted with chemicals, bacteria and germs. There are also many particles that cause people to have allergic reactions such as headaches and red eyes, as well as digestive problems, dizziness, chronic fatigue, congestion and many other chronic and acute diseases. A HEPA filter can provide relief. Some of the benefits reported by those who use a HEPA filter are that they are healthier, sleep better and have more energy.

There are several different categories of HEPA filters:

• True HEPA filters. These filters are tested to ensure they will filter with 99,7% efficiency. They must have seal attached to them certifying that they have been tested with a serial number and the test results are printed here as well. They are more expensive and must perform to the standard.
• HEPA type filters. They look much like the true filters but are not tested to perform to the 99.7% efficiency rate. They are not as expensive and will only capture 85-90% of the particles in the air.

You can easily tell the difference between true and replica HEPA filters by checking for the seal of authenticity.

HEPA filters trap small particles in the air. The more square feet you have in the filter media, the more particles it can remove from the air before it needs to be changed. It will also be able to remove more impurities from the air each time it passes over filter. It is very important to have a good quality filter because the pleats need to be uniform to give each one the same filtration efficiency. If the pleats are too close together they may actually restrict the air flow and there will not be as much air flow as you need.

The material used in the filter is very important. Some filters use synthetic material, but thin paper is the best. It is the most effective at removing the harmful particles without restricting the air flow. This material is easy to damage when you are handling it so the air purifier has to be designed in such a way that it also protects the filter.

Most air filters use a method called impingement to purify the air and trap the airborne particles. HEPA air filters use this method by using fine materials, such as thin paper, through which they draw the air. The particles in the air become trapped on the material and the air that flows back into the room is clean.

There are drawbacks to relying totally on a HEPA filter to purify the air in your home or office. They cannot capture any particles that are smaller than 0.3 microns and do not treat such things as gases, odors and viruses. Because the air must pass through a filter, it is hard to purify the air in a large room. Because they need to be constantly exchanging the air, they also tend to be noisy. Even though many different types of air purifiers have been developed, most experts tend to rely on the HEPA filter as being the most effective.