High Efficiency Particulate Air (HEPA) is a type of air filter designed to remove particles and pollutants from the air. The key feature of HEPA filters is their ability to capture extremely small particles, as small as 0.3 micrometers, with high efficiency. These filters are constructed from a mat of dense, randomly arranged fibers, often made of glass. The intricate web of fibers creates a maze-like structure that intercepts and traps particles as air passes through.

HEPA filters operate on the principle of mechanical filtration. When air flows through the filter, particles are captured by different mechanisms, including interception, diffusion, and inertial impaction. Larger particles are caught directly by the fibers, while smaller ones are forced to change direction and collide with the fibers, ultimately getting trapped.

HEPA filters find widespread use in various applications where air quality is crucial. They are commonly employed in air purifiers, vacuum cleaners, and ventilation systems to remove airborne contaminants such as dust, pollen, mold spores, pet dander, and bacteria. Due to their high efficiency, HEPA filters are particularly valuable in environments that demand clean air, such as hospitals, laboratories, and cleanrooms. The effectiveness of HEPA filters in capturing a wide range of particles makes them an essential component for maintaining healthy indoor air quality in diverse settings.