Dr Will Hick's commentary appears in this article. We are grateful to Market.com for reaching out to us.

He says:
Indoor air quality can change quickly due to cooking, cleaning, or outdoor pollution entering the home. Air purifiers all aim to do the same thing: clean the air from these different sources. However, how they do it, and how effective they are, can vary quite a lot.

In practice, a purifier’s effectiveness depends on how much air it can clean per hour relative to the room size, something often summarised by measures such as ‘clean air delivery rate’.

Most entry level models rely on a fan and a basic particle filter. These are effective at removing dust, pollen, and other larger airborne particles. As you move up the price range, you’ll often find higher grade HEPA filters, which capture very small particles such as PM2.5, alongside thicker activated carbon filters that remove gases from traffic pollution, cooking fumes, and everyday odours through adsorption.

More advanced units also tend to have stronger, yet quieter fans, allowing them to clean and ventilate  a room faster without becoming intrusive. Many modern purifiers now include built in air quality sensors providing users with helpful data, with some models automatically adjusting their power when pollution levels rise.

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