What is the Difference Between a HEPA Filter and a True HEPA Filter?

HEPA filters and True HEPA filters are two of the most popular air filtration devices used in the air purifier industry. While they may look similar, there are some key differences between the two that make them unique. The main difference between the two is their filtration efficiency. In general, a HEPA-type filter has an efficiency rate of 99% for capturing particles as small as 2 microns, while a True HEPA filter has an efficiency rate of 99.97% for particles as small as 0.3 microns.

HEPA stands for High-Efficiency Particulate Air filter and is the only type of filter that meets the DOE standards for HEPA filtration, has the highest efficiency, and reaches the 99.97% threshold. To be considered a true or genuine HEPA filter, it must meet certain requirements, such as the ability to trap 99.97 percent of particles that are 0.3 microns in size. HEPA filters usually have a pleated design with some mesh elements, to trap particles. They are mainly made of fiberglass compared to a blend of cellulose (20%) and polyester (80%) for True HEPA filters.

Medical-grade HEPA filters, generally advertised as H13 filters, supposedly outperform normal HEPA filters. Efficiency describes the percentage of particles that a device removes from the air passing through it, while effectiveness refers to how well a device cleans the air in a room. A filter that is too small or inadequate can be ineffective in a situation, even if it has a high efficiency, whether it is true HEPA or HEPA-type. True HEPA filters are tested for efficiency when fed with a 0.3 micron particle cloud. The density of the particles is measured before and after passing through the filter, and the efficiency is calculated from these values.

A common leak point is the frame around the filter itself, but there can also be leaks along any passage leading to the filter in a device such as a portable air cleaner or vacuum cleaner. In addition to their filtration efficiency, another difference between HEPA-type and True HEPA filters is their cost. The HEPA-type filter is often combined with the compact and more economical air purifier while the true HEPA filter is labeled with the largest premium air purifier. When looking for air filters, it's important to understand what makes a true or genuine HEPA filter so you can make an informed decision about which type of filter is best for your needs. True HEPA filters are more efficient than their counterparts and can help improve air quality in your home or office.

Wilbert Cromley
Wilbert Cromley

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