Types of Air Purifier Filters

Air Purifiers may use a wide variety of technologies to filter the air. For particulate pollution including PM2.5, pet allergens, pollen and hazardous gases, the three most common filter types are:

1. UV light filters

These are designed to kill bacteria. However, US Environmental Protection Agency claims most UV filters don’t even kill bacteria. This is because the air passes too quickly through the UV light.

UV light filters

Conclusion: UV filters won’t protect you from PM2.5, pollen or hazardous gases.

2. Activated carbon filters

These filters use charcoal to capture certain chemicals and organic matter. Carbon will capture things like formaldehyde and other volatile organic compounds (formaldehyde testgeneral VOC test).

Activated carbon granules

Conclusion: Carbon filters can capture hazardous gases. They cannot capture particulate pollution like PM2.5 and pollen or pet allergens.

3. HEPA Filters

A type of filter made from synthetic fibres that trap particles (even the tiny ones 0.3µm or below). As such, HEPA filters can capture particulate pollution like PM2.5 and pollen.

HEPA filters

Conclusion: For those living in polluted areas, or if your concern is pollen or pet allergens, a HEPA filter is what you need.


Smart Air offers certified and tested HEPA filters and Activated Carbon Filters, depending on your need. Learn about each type of filter we offer in our shop.

Smart Air HEPA filters

Smart Air is a social enterprise that creates simple, no-nonsense air purifiers and provides free education to protect people’s health from the effects of air pollution. We are proud to be the only certified B-Corp dedicated to fighting air pollution.