These are special kinds of filters that have been designed to meet the requirements expected by the HEPA standards. One of the conditions is the air filter should be able to eliminate up to 98% of any particles which are larger. There are many good reasons why Hepa filters are used nowadays. First of all, the manner in which they have been designed has adapted it well for the usual functions.
They are usually made of fiber glass and the thickness and diameter has been configured in specifications that make the filters to work in an effective manner. These filters work like a sieve and the larger particles cannot pass through the main opening. However, the Hepa filters have been made in order to trap the small pollutants within the air and this is usually done with help of some special mechanisms.
Mechanisms used with Hepa filters
With the invention of the newest technology in this sector, there are three main ways in which filtering is done. Through the interception method, a given flow of particles within the air are directed towards one direction and later trapped by the fibers since they will stick to the radius of the filter. Another common system is the impacting stage where only the larger particles are targeted. In this case, there are usually curving contours within the air which are later directed and the whole process is usually quickened with high-speed of air flow. Another common mechanism used with HEPA Filter Air Purifier is the diffusion method where there is some collision of the gas molecules that are later delayed in their course of movement; and once this happens, it means the particles will later become dominant since the velocity will be far below.
The Hepa filters have been specially configured to trap the fine particles within the air through there is no filtration of gases. Some of the substances that are prone for this kind of filtration include chemical vapors, cigarette odors among others. After the manufacturing process, a complete Hepa filter needs to have a filtration unit.
History of Hepa filters
It dates back in 1940 when they were used to control the spread of some airborne contaminants. Things have been changing over the decades and there has been need to modify these filters in a way that will enable them to meet some demands basing on the quality of air within the space. Nowadays, we are in the era of industrialization and things have only become much complicated through the emission of gases from hospitals, nuclear power, computer chips among others. Nowadays there are filters that are more specialized to take care of special conditions such as acute tuberculosis; really they have been perfect when it comes to controlling the spread of infectious airborne bacteria since they have UV rays to kill the micro organisms.