Views: 5 Author: Site Editor Publish Time: 2018-06-04 Origin: Site
Before you know why you need a HEPA air purifier, you should know that why you need an air purifier.
Air purifier will improve your health. The Environmental Protection Agency (EPA) estimates that, on average, indoor air is two to five times more polluted than outdoor air. This includes common allergens like pollen, dust mites, pet dander, and mold spores but also exhaust emissions, smoke, VOCs, and other chemical vapors.
HEPA stands for High Efficiency Particulate Air. HEPA air purifiers were originally developed by the Atomic Energy Commission to capture radioactive dust particles. By definition, a HEPA filter are tested to certify that they remove at least 99.97% of all particles 0.3 microns and larger.
What is a micron?
Air purifiers are designed to eliminate impurities in the air, even those impurities which are so microscopic that they are invisible to the naked eye. Microns are is the common measurement term used for these microscopic airborne particles. One micron is 1/25,000 of an inch. To give you an idea of how small this is, dust mites average around 200-300 microns, and a grain of sand can be over 800 microns!
How do HEPA air purifiers work?
Usually, dirty air is inhaled into the air purifier, and in most HEPA air purifiers, the washable pre-filter captures larger, visible parts. Then the air usually passes through the HEPA filter. The HEPA filter medium consists of millions of ultrafine glass fibers that combine to form a material that feels a bit like paper. During manufacturing, the best HEPA filter media is rolled and folded in warm conditions to prevent any cracks or terminology. As as passes through them, allergens of all different sizes, such as pollen, animal dander, mold spores, and dust get trapped in the tiny filaments of the filter.
Many HEPA air purifiers also contain a carbon filter to capture chemicals, odors, and gases. Once the dirty air has passed through all the filtration stages, the now cleaned air is sent back into the room.