When it comes to air purification, ULPA and HEPA filters are two of the most popular options. But what are the differences between them? ULPA filters are more effective at trapping smaller particles than HEPA filters, with 99.999% efficiency at removing particles 0.12 microns in diameter or greater, compared to 99.97% for HEPA filters. Both ULPA and HEPA filters are created by compressing numerous layers of fiberglass into an elaborate network of paper-like sheets, but ULPA filters are thicker than HEPA filters. To meet the minimum standard set by the Department of Energy, HEPA filtration must trap at least 99.97% of all particles larger than 0.3 microns, while ULPA filters must be 99.999% efficient and capable of removing particles smaller than 0.12 microns.
For those tasked with minimizing dust and airborne pathogens during construction in healthcare environments, HEPA filters remain the recommended standard. However, ULPA filters may be necessary for specialized applications such as microelectronics manufacturing or medical laboratories, removing cleanroom particles, or filtering toxic surgical plumes emitted during operations electrosurgical. If you looked at the actual filter of a HEPA or ULPA purifier, it would look a lot like folded paper. Efficiency measures the filter's ability (over the life of the product) to remove airborne particles. The Filter King online store has HEPA filters from several different MERVs, and in virtually any size you can imagine.
The only material difference between a HEPA filter and a ULPA filter is the density of the borosilicate fibers. A more relaxed HEPA filter accounts for approximately 75% of the cost of an ULPA filter and can last up to twice as long. When air is forced through the fine mesh filter, particles are trapped and cannot re-enter the atmosphere.