How many grades are there for air filters, such as H12?

The classification of air filters is mainly based on international standards, with the core indicator being the filtration efficiency of particles of a specific size. Common classification systems and key grades are as follows:

1. European EN 1822 standard (most commonly used)

This is the mainstream classification standard for high-efficiency particulate air ( HEPA) and ultra-high-efficiency particulate air (ULPA) filters, based on their filtration efficiency for particles of 0.1~0.3μm:

HEPA ratings: H10 (≥95%), H11 (≥99.5%), H12 (≥99.95%), H13 (≥99.97%), H14 (≥99.995%).

ULPA ratings: U15 (≥99.9995%, for 0.12μm particles), U16 (≥99.99995%), U17 (≥99.999995%).

2. Traditional US standards (which have been gradually replaced by ISO)

In the early FS 209E standard, HEPA corresponds to an efficiency of ≥99.97% for filtering 0.3μm particles (similar to H13); ULPA corresponds to an efficiency of ≥99.999% for filtering 0.12μm particles (similar to U15).

3. International ISO 16890 standard

Based on their filtration efficiency for PM1, PM2.5, and PM10, they are divided into levels from e10 to e18 (e.g., e12 corresponds to PM1 filtration ≥70%), but the commonly mentioned "H12" and "H13" are still mainly based on the EN 1822 standard.

Among them, H12 grade belongs to the HEPA category, with a filtration efficiency of ≥99.95% for particles of 0.1~0.3μm, and is commonly used in cleanrooms, medical equipment, and other scenarios with medium cleanliness requirements. The higher the grade number, the more stringent the filtration accuracy and efficiency.