How is the air purifier filter grade divided?
At present, the air purifier filters on the market generally contain three layers of filters, and the better air purifiers have five or more layers of filters.
Filter classification:
1. Pre-filter
Pre-filter, also known as primary filter, is the first filter of purifier It can filter out large particles of dust and suspended solids in the air, and dust, hair and other objects can also be blocked by it. The pre-filter also has the function of protecting other filters.
2. Activated carbon filter
Activated carbon filter can effectively remove odor and odor in the air, and can effectively adsorb and purify second-hand smoke, formaldehyde, benzene, carbon monoxide in the air and other harmful gases. The better the activated carbon filter material, the stronger the purification function.
3.HEPA filter
HEPA filter is a high-efficiency filter, which is interwoven by very fine organic fibers, with high purification efficiency. It can efficiently filter and purify more than 70 kinds of pollutants such as bacteria, viruses, fungi, pollen and asbestos suspended in the air, and the purification rate for 0.3 micron particles is 99.97%.
Knowledge expansion:
HEPA filters are subdivided into G1-G4, F5-F9, H10-H14 and U15-U17 according to the current European grades. Common in the field of air purifiers is the H grade, of which H13-14 is recognized as a better filter.