Air filter classification standards

Air filters are generally classified into several grades based on their filtration efficiency, such as primary, medium, high, and ultra-high efficiency, with specific standards varying by country.

Chinese standards

According to Chinese national standards, the classification of air filters is as follows:

Coarse filters: Suitable for filtering larger particles and are used for primary filtration typically.

Medium-efficiency filters: Used for filtering particles ranging from 1 to 10 microns and are suitable for placement before high-efficiency filters.

High-medium efficiency filters: Applicable for higher filtration requirements.

Sub-high-efficiency filters: Have filtration efficiency between medium and high-efficiency filters.

High-efficiency filters (HEPA): With high filtration efficiency, they are suitable for high-demand environments such as cleanrooms.

Ultra-high-efficiency filters (ULPA): Have even higher filtration efficiency and are suitable for extremely high cleanliness requirements.

Relevant standards include "Air Filters" GB/T 14295-2008 and "High-Efficiency Air Filters" GB/T 13554-2008.

European standards

In Europe, the grades of air filters are mainly classified according to the EN779 and EN1822 standards:

Primary filters: G1-G4 grades, suitable for basic filtration.

Intermediate filters: F5-F9 grades, suitable for filtering smaller particles.

High-efficiency filters: H10-H14 grades, suitable for environments with high cleanliness requirements. T 14295-2008 and "High-Efficiency Air Filters" GB/T 13554-2008.

The standards of the United States

The air filter standards in the United States mainly include ASHRAE 52.2 and IEST-RP. They are usually classified into primary, intermediate and high-efficiency filters.

Filter efficiency

Primary filters: G1 level (filtration efficiency < 65%), G2 level (65% - 80%), G3 level (80% - 90%), G4 level (> 90%).

Medium-efficiency filters: F5 level (suitable for pharmaceutical, food industries), F6 level (suitable for offices), F7 level (suitable for biomedicine industries), F8 level (suitable for fiber manufacturing, etc.).

High-efficiency filters: H10 level (filtration efficiency ≥ 85%), H11 level (≥ 95%), H12 level (≥ 99.5%), H13 level (≥ 99.95%), H14 level (≥ 99.995%).

By understanding these standards, users can select the appropriate air filters according to their specific needs, thereby ensuring the air quality and the normal operation of the equipment.