Odds are you hae heard of a HEPA filter. With that said, if you’re like a considerable majority of people, you really don’t know what a HEPA filter really is nor how it works. HEPA stands for high-efficiency particulate air filter. We present for your consideration specific information about how a HEPA filter works.
Design and Construction of a HEPA Filter
Technically speaking, there isn’t a specific standard regarding the manner in which a HEPA filter is to be made. With that noted, nearly all HEPA filters are designed and constructed using glass fibers. The fiberglass used in a typical HEPA filter usually is a few hundred microns across.
What is unique about a HEPA filter is that instead of being woven in some manner, these fiberglass strands or threads are pressed into sheets in whatever way or direction each fiber happened to be facing. In turn, each of these sheets are pressed together in a kind of sandwich pattern.
Functionality of a HEPA Filter
The functionality of a HEPA filter involves air flowing across rather than through the fiberglass membranes that make up the filter. The manner in which this works renders a HEPA filter more effective than a “flat filter.” A primary reason why this is the case is because of its design a HEPA filter has a larger effective surface area. As a result of the larger filtering surface area, a HEPA filter is more efficient and has a longer useful life than other filtering products, by design. Because of the layered design of a HEPA filter, it takes a more significant amount of time to clog when contrasted with other filter products on the market today.
Most significantly, because of the design and functionality of a HEPA filter, it is considerably more effective at eliminating harmful pathogens like bacteria and viruses. A HEPA filter enhances the overall safety of a person using this type of product for activities like biohazard cleanup or biomatter remediation.
HEPA Filter Compared With Alternatives
In this day and age, there are three other types of filtering systems that are used with some frequency. These are:
- Activated carbon
When contrasted with the other more commonly utilized filtering systems, the HEPA filter ranks at the most broadly functional and effective end of the range. A HEPA filter is ranked as excellent at filtering out some of the more commonplace airborne particulates. These include:
- Pet dander
- Mold spores
- Dust mite excrement
As an aside, a HEPA filter is considered slightly better at filtering out bacteria than viruses. A HEPA filter is not capable of filtering out gasses like radon or formaldehyde. An activated carbon filter is needed to address and filter out these types of gasses.
Applications of a HEPA Filter
Because of the types of contaminants a HEPA filter eliminates, this is an ideal product to be used for biohazard cleanup, also known as biohazard remediation. Indeed, this is the recommended filter to utilize when undertaking infectious disease disinfection.
In addition to being useful as part of personal protective equipment for infectious disease disinfection, there are other common uses for HEPA filters as well. These include:
- Vacuum cleaners
- Motor vehicles
Lifespan of a HEPA Filter
When it comes to fully understanding how a HEPA filter works or functions, it is helpful to know the useful life of this type of product. A HEPA filter cartridge typically has a useful life of between two to three years. This is contrasted with an activated carbon filter that lasts between three months to one year. An ultraviolet filter lasts for about one year. An electrostatic filter lasts indefinitely but requires regular cleaning.
History of a HEPA Filter
The idea underpinning the eventual development of the HEPA filter were gas masks worn my military personnel during World War II. German soldiers had placed a piece of paper in gas masks. This addition proved remarkably effective at capturing certain types of potentially harmful chemical smoke. In turn, the British military manufactured gas masks similar to what German soldiers were using.
During the Manhattan Project, another precursor to today’s HEPA filter was designed and developed. The Manhattan Project was the program dedicated to designing and building atomic bombs and associated technology for use by the United States. This derivation was used by the U.S. Army Chemical Corps and the National Defense Research Committee as a means of removing radioactive materials from the air.
By the 1950s, the HEPA filter was commercially marketed. Indeed, “HEPA’ was trademarked. Ultimately, the term HEPA became widely used to identify this type of filtering product and not a specific brand. Since its introduction onto the market in the 1950s, the HEPA filter has been one of the most trusted types of products in its class.