Isnt it a bit confusing reading about all the different types of air-purifiers that are available in the market today? If you were to do a search on the Internet for air-purifiers you will be presented with literally thousands of websites, all of which sell a variety of air purification machines. One of the most popular air-purification systems is a HEPA air purifier. HEPA Filters An acronym for high efficiency particulate arresting, a HEPA filter theoretically is capable of removing almost 99.97 % of airborne particles of .3 micrometers or larger. These would include common irritants and allergens like dust, pollen, mold and bacteria. The original HEPA filter was designed in the 1940s during the Manhattan Project by the US Atomic Commission to prevent the spread of airborne radioactive contaminants which were a result of atomic bomb testing. These were made commercially available in the 1950s and HEPA became the registered trademark and a generic name for highly efficient filters. Over the years HEPA filters have been further developed to satisfy a greater demand for air purity not only in homes but also in various industries like aerospace, electronic micro circuitry, biopharmaceutical labs, and in office and commercial complexes. There are also Ultra-HEPA or ULPA filters available whose ability to filter dust and other contaminants is even better than HEPA filters. It filters out 99.99% of the contaminants. True HEPA filters, are excellent for removing all types of contaminants that are greater than .3 microns in size. One micron is approximately one hundredth times smaller than the width of your hair. So, you can visualize just how tiny .3 micron is and the capability of this filter to be able to trap and remove such particles. Thus when buying a HEPA filter do ensure that youre buying a true HEPA filter and not a HEPA type filter as the efficiency of the latter ranges from 25-95%, while true HEPA filter is 99.97% efficient in removing airborne particles. In addition, HEPA filters provide a dry environment, ensuring the complete elimination of the trapped bacteria as it cannot survive in dry conditions. Some filters are chemically treated to kill bacteria while others may include a germicidal ultra violet light to achieve the same effect. HEPA air purifiers are noisier than other filters because they use a motorized fan to suck in the air. However, when purchasing the purifier one must note the performance of the fan motor as a weak motor will not be able to draw in satisfactory amount of air for the purifier to be effective. The filter usually needs to be replaced every 12-18 months, depending on the usage of the purifier. The life span of a HEPA filter usually ranges from two to five years. By and large HEPA air purifiers are rated the best in terms of overall performance and ability to filter out microscopic particles. |
