What is the name of the air filtration device that removes 99.97 percent of airborne particulates 0.3 micron or greater in diameter?

What is the name of the air filtration device that removes 99.97 percent of airborne particulates 0.3 micron or greater in diameter?

• A. HEPA filter
• B. ULPA filter
• C. Carbon filter
• D. Ionizing filter

Answer: (A)

HEPA filters are defined by their ability to remove at least 99.97% of particles that are 0.3 microns in diameter. That 0.3-micron size is the most penetrating for fibrous filters, so achieving this efficiency there ensures strong performance across a range of particle sizes. The filter works through a combination of diffusion (for very small particles), interception, and inertial impaction (for larger particles) as air passes through the dense media. This makes HEPA filtration a standard choice in infection-control settings to reduce airborne particulates, including many bacteria and spores. Other filter types either target gases (carbon filters) or use ionization, or offer different efficiency characteristics, but they do not match the 99.97% at 0.3 microns specification. Thus, the device described is a HEPA filter.

HEPA filters are defined by their ability to remove at least 99.97% of particles that are 0.3 microns in diameter. That 0.3-micron size is the most penetrating for fibrous filters, so achieving this efficiency there ensures strong performance across a range of particle sizes. The filter works through a combination of diffusion (for very small particles), interception, and inertial impaction (for larger particles) as air passes through the dense media. This makes HEPA filtration a standard choice in infection-control settings to reduce airborne particulates, including many bacteria and spores. Other filter types either target gases (carbon filters) or use ionization, or offer different efficiency characteristics, but they do not match the 99.97% at 0.3 microns specification. Thus, the device described is a HEPA filter.