HEPA filters are air filters that are designed to capture at least 99.97% of dust, pollen, mold, bacteria, and any airborne particulate matter with a size of 0.3 microns (µm). Developed by the Department of Energy (DOE) after the Manhattan Project in the 1940s, HEPA stands for High-Efficiency Particulate Air filter. The high-quality HEPA filter of the second phase is able to capture even the finest particles that escape from the prefilter. HEPA filters are widely used in both commercial and residential settings as they are essential to prevent the spread of bacterial and viral organisms in the air and, therefore, of infections. A HEPA air filter is made up of thousands of extremely fine fibers arranged in a matte shape to intercept both microscopic and larger particles.
This technology was born from the gas masks worn by soldiers fighting in World War II. If a HEPA filter is not changed in time, stress will be generated in the machine or system and particulates will not be removed from the air properly. To make sure that these contaminants are efficiently removed, taking advantage of ionization technology allows more debris to be captured in the air so that the HEPA filter can do its job more efficiently. The carbon prefilter also captures smoke, odors, harmful gases, and volatile organic compounds (VOCs), which HEPA filters cannot trap. A properly chosen HEPA filter can ensure that these contaminants are efficiently removed, greatly improving the quality of the air you breathe. Therefore, if a HEPA filter removes 99.97% of particles that are 0.3 microns in size, it is even more effective at eliminating PM10, PM2.5 and larger allergens. Although HEPA filters are fantastic, there are times when it would be better to use an air purifier without a filter.
For example, if you want to eliminate the microbes and bacteria present in the air, a model that works by incinerating particles will destroy more than 99.99% of microorganisms. This is beneficial for asthmatics and allergy sufferers since the HEPA filter traps fine particles (such as pollen and feces from house dust mites) that cause allergy and asthma symptoms. Unlike sieves or membrane filters, through which particles smaller than openings or pores can pass through, HEPA filters are designed for a variety of particle sizes. This means that they can be used in any environment - industrial, commercial, healthcare or by consumers - to capture airborne contaminants.