Standard ISO 29463 Print

ISO 29463 is the new global standard for HEPA filters' testing and classification, it replaced EN1822.

The new standard has its roots in EN 1822, and defines 13 different filter classes ranging from ISO 15 E to ISO 75 U.

ISO 29463 maintains the EPA, HEPA und ULPA filter classes as specified in EN 1822. Evaluation in the new ISO standard is also based on particle arrestance at MPPS (Most Penetrating Particle Size). MPPS is the particle size at which an air filter shows minimum arrestance.

However, there is one difference in particulate filter classification between the two standards. EN 1822 classifies a particulate filter with an arrestance of e.g. 99.9993 % at its MPPS as HEPA filter class H14. When evaluated according to ISO 29463, however, this same air filter is classified as ULPA filter class ISO 50 U. As a ULPA filter under ISO 29463, it is subjected to other leakage test procedures than is the case under EN 1822.

Furthermore the ISO 29463 starts with the filter group ISO 15 E, which is equivalent to the filter class E11 according EN 1822. Consequently does not cover a counterpart to the EPA filter class E10. In contrast shows the test standard ISO 16890 with the filter group ISO ePM1 >95% an equivalent to the filter class E10.

Here is a compararison between the filter classes defined in ISO 29463 and EN 1822:

Overall Value Local Value
Filter Classes 
according EN 1822
Filter Classes 
according ISO 29463
Efficiency Penetration Efficiency Penetration
E10 - ≥ 85% ≤ 15% - -
E11 ISO 15 E ≥ 95% ≤ 5% - -
ISO 20 E ≥ 99% ≤ 1% - -
E12 ISO 25 E ≥ 99.5% ≤ 0.5% - -
ISO 30 E ≥ 99.90% ≤ 0.1% - -
H13 ISO 35 H ≥ 99.95% ≤ 0.05% ≥ 99.75% ≤ 0.25%
ISO 40 H ≥ 99.99% ≤ 0.01% ≥ 99.95% ≤ 0.05%
H14 ISO 45 H ≥ 99.995% ≤ 0.005% ≥ 99.975% ≤ 0.025%
ISO 50 U ≥ 99.999% ≤ 0.001% ≥ 99.995% ≤ 0.005%
U15 ISO 55 U ≥ 99.9995% ≤ 0.0005% ≥ 99.9975% ≤ 0.0025%
ISO 60 U ≥ 99.9999% ≤ 0.0001% ≥ 99.9995% ≤ 0.0005%
U16 ISO 65 U ≥ 99.99995% ≤ 0.00005% ≥ 99.99975% ≤ 0.00025%
ISO 70 U ≥ 99.99999% ≤ 0.00001% ≥ 99.9999% ≤ 0.0001%
U17 ISO 75 U ≥ 99.999995% ≤ 0.000005% ≥ 99.9999% ≤ 0.0001%