Usually there are 3 types of air filter in air purifier. They are HEPA filter, activated carbon filter and prefilter. Different filters have different functions. Prefilter is in the first layer which can filter some large particle of dust. HEPA filter can filter out the 0.3 micron dust. And activate

The principle of adsorption of activated carbon is to form a balanced surface concentration on the surface of the particles. The size of the activated carbon particles also has an effect on the adsorption capacity.

With the development of industry, in order to purify the air quality, air filters are very popular. You will have a lot of questions in the process of purchasing and using air purifiers. This article will answer the common questions for you.