Conventional HEPA filter
Xiaomi's High-Efficiency Filter
![Xiaomi Smart Air Purifier 4 Filter](https://cdn.statically.io/img/i02.appmifile.com/645_operator_sg/15/10/2021/8959b605fe8e40b131e1185973a28e91.png)
Less clean air
![Xiaomi Smart Air Purifier 4 Filter](https://cdn.statically.io/img/i02.appmifile.com/783_operator_sg/15/10/2021/a020ffbb39ce9db10745788d8701659f.png)
More clean air
The HEPA filter is made of dense fibreglass to trap particles, which means that less clean air gets through the filter.
Xiaomi's filter uses melt-blown PP fibres with electrostatic technology. With greater space between fibres, larger volumes of air are able to pass through the filter.
![Xiaomi Smart Air Purifier 4 Filter](https://cdn.statically.io/img/i02.appmifile.com/322_operator_sg/15/10/2021/d123b7bd7709a3d6bce71bc6c506a9b0.png)
Noisy
![Xiaomi Smart Air Purifier 4 Filter](https://cdn.statically.io/img/i02.appmifile.com/389_operator_sg/15/10/2021/cdb94695d5077a5ca2892a865d2d6e23.png)
Low noise
Large volumes of air are forced through the dense HEPA filter, meaning a higher fan speed is required, which generates more noise.
With a lower fibre density, the filter allows air to pass through at high speeds, resulting in less noise.
![Xiaomi Smart Air Purifier 4 Filter](https://cdn.statically.io/img/i02.appmifile.com/880_operator_sg/15/10/2021/34116730afdaad4818ad7afd7687650d.png)
Higher energy consumption
![Xiaomi Smart Air Purifier 4 Filter](https://cdn.statically.io/img/i02.appmifile.com/972_operator_sg/15/10/2021/bb0fe3623a43ea58865286d15b0ec4d4.png)
Lower energy consumption
In order for the HEPA filter to release more clean air, the motor must run at a higher speed, which translates into a higher energy consumption.
With a lower fibre density, Xiaomi's filter is able to release the same volume of clean air as a conventional filter, but with a much lower energy consumption.