Views: 8 Author: Site Editor Publish Time: 2018-11-01 Origin: Site
If you are looking for an air purifier, you may have meet the HEPA filter. Perhaps you want to know what HEPA air filters are, or you've heard about HEPA filters before, and you might wonder how it works. HEPA filtration is an important and popular air purification technology. You can try to understand the air purifier and make a purchase decision.
What is the HEPA filter?
HEPA is the acronym for high-efficiency particulate air, so HEPA filters are high-efficiency particulate air filters. Filters, whether used in air purifiers or other implementations, have many advantages and requirements.
What sets HEPA filters apart from the rest is their claims are more than just claims. Because in order to be called a true HEPA filter it has to be first be tested and approved, you know exactly what to expect. The Institute of Environmental Sciences and Technology dictates that a HEPA filter must trap 99.97% of particulates 0.3 microns or larger. This does not mean that the filter cannot trap particles smaller than 0.3 microns, because many HEPA filters can; it is simply the threshold that must be reached in order to carry the HEPA name.
What is a micron?
Particles range from ultra-microscopic to entirely detectable to the human eye. Microns, which are one-millionth of a meter, are how particles are measured. To give you a better idea of the size of a micron, or less than a micron, consider that we cannot visually see anything less than 10 microns. Bacteria can be anywhere from 0.3 to 60 microns, and 1 inch equals 25,400 microns.
How do HEPA filters work?
To put it simply, HEPA filters trap air contaminants in a complex web of fibers. Depending on the size of the particle, this can happen in four different ways: Inertial Impaction, Diffusion, Interception, or Sieving.
Through inertial impaction and sieving,the larger contaminants can be trapped.The particles are trapped when it collide with the fibers or are trapped when attempting to travel through the fibers. When the medium sized particles move through the filter, they are grabbed by the fibers via direct interception. It will be dissipated as the smaller particles travel through the filter and eventually collide with a fiber and are trapped.