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High efficiency particulate air (HEPA) filters and ultra-low particulate air (ULPA) filters are air filters designed to trap a vast majority of very small particulate contaminants from an air stream. HEPA & ULPA Filters are similar in many aspects, but they differ in many aspects either. Now let's learn following information about HEPA VS ULPA filters.

First and foremost, HEPA & ULPA Filters are different in definition and efficiency. HEPA filters are capable of removing 99.97% of contaminant particles 0.3 μm in diameter. Most standards also specify that HEPA filters must feature minimal pressure drop and maximum airflow when in operation. ULPA filters are closely related to HEPA filters but are even more efficient. ULPA filters are specified to remove 99.999% of contaminants 0.12 μm or larger in diameter.

What's more, HEPA VS ULPA filters in working principle. HEPA & ULPA Filters media is made up of countless randomly-arranged fibers which together form a dense mat; when air flows through the filter, the media captures and contains contaminant particles throughout its depth. Filter fibers trap contaminants using three primary methods - interception, inertial impaction and diffusion. Understanding these three methods makes it clear why particles around 0.3 micrometers are most difficult to filter. Particles less than 0.1 micrometers are easily trapped due to diffusion while particles larger than 0.4 micrometers are trapped by inertial impaction. Particles between 0.1 and 0.4 μm are therefore too large for effective diffusion and too small for inertial impaction and efficient interception, so that the filter's efficiency drops within this range.

HEPA filters rated 99.99% efficient with particles 0.3 microns and larger in diameter, while ULPA filters rated 99.999% efficient with particles 0.12 microns in diameter

Last but not least, HEPA & ULPA Filters share similar applications. HEPA and ULPA filters are used in applications requiring very efficient filtering of airborne pathogens which can cause aggravate asthma and cause allergies or disease. These filters are also useful in manufacturing environments which require very clean air. Some applications include airline cabin air purifiers, biomedical air filtration, electronics manufacturing, pharmaceutical manufacturing and vacuum cleaner filters.

After learning the information of HEPA VS ULPA filters, you must know the difference between HEPA & ULPA Filters. Both of them play an important role in modern society. Shanghai Hefil supplies a wide range of both High Efficiency Particulate Air (HEPA) and Ultra Low Penetration Air (ULPA) filters. Each filter is carefully designed, manufactured and tested. If you are in need of HEPA & ULPA Filters, you can visit www.hefilter.com for more information.