How are the filtration efficiency levels of high-efficiency filters classified?

The classification of HEPA filter filtration efficiency levels is mainly based on international and domestic standards. The core principle is to define the filtration efficiency for particles of a specific size. Common standards and levels are as follows:

International Standard ( ISO 16890)

Based on their filtration efficiency for PM1, PM2.5, and PM10 particles, they are classified as follows:

e10: PM10 filtration efficiency ≥50%;

e11: PM2.5 filtration efficiency ≥60%;

e12: PM1 filtration efficiency ≥70%;

e13: PM1 filtration efficiency ≥80%;

e14: PM1 filtration efficiency ≥90%;

e15: PM1 filtration efficiency ≥95%;

e16: PM1 filtration efficiency ≥99%;

e17: PM1 filtration efficiency ≥99.9%;

e18: PM1 filtration efficiency ≥99.99%.

Domestic and traditional standards ( GB/T 13554-2020)

Based on the filtration efficiency for 0.3μm monodisperse aerosols, the core grading includes:

High-efficiency particulate air (HEPA) filter : filtration efficiency ≥99.97% (corresponding to H13 grade in US Federal Standard FS 209E);

Ultra-high efficiency filter ( ULPA): filtration efficiency ≥99.999% (for 0.12μm particles, corresponding to U15 and above).

In addition, the European EN 1822 standard is also commonly used, which classifies filtration efficiency into H10 to H14 (HEPA) and U15 to U17 (ULPA) based on the efficiency for 0.1-0.3μm particles. The higher the number, the more stringent the filtration efficiency requirements. In practical applications, the choice of filtration level needs to be determined in conjunction with cleanliness requirements (such as medical, electronic, and laboratory scenarios).