How does a HEPA filter work?
A HEPA air filter is designed with intricate layers, in order to catch particles of microscopic size. Usually made from materials like PTFE or glass-fibre, each layer is arranged in randomly arranged sheets, which come together to form a kind of mat. Because particulate matter ranges in size, a HEPA filter traps in three different ways:
- Larger particles: are trapped through impact, by hitting and sticking to a net-like formation of filter fibres.
- Smaller particles: are intercepted as they move through air, becoming stuck on filter fibres.
- Smooth particles: are the hardest to capture as they move through air flow randomly. The HEPA air filter is designed so that smooth particles collide with filter fibres as they move erratically with air.