The International Organization for Standardization (ISO) has created a new global standard, ISO16890, which defines the classification and testing procedures for air filters used in general ventilation systems.
The new international ISO 16890 standard came into force on 1 January 2017, but only replaced the previous standard in May 2018.
The most important change concerns the filter classification criteria, which are classified according to capacity to filter fine dust, generally referred to as PM10, PM2,5e PM1.
PM stands for "Particulate Matter". The abbreviation refers to the suspended particles present in the air that we breathe every day, usually called fine dust or particulates. The number following the initials PM, for example, 10, indicates the diameter size of the particle, which can vary from 10 to 1 micron.
. – particulate made up of particles with a diameter of less than 1 µm and up to 0.3 µm.
The new parameters have international significance, dictating standards applicable all over the world. ISO 16890 replaces the European standard EN 779 and ASHRAE 52.2 (the US market standard).
ISO 16890 tests filters with particles from 0.3 µm to 10 µm. The previous EN 779 only tested particles with a diameter of 0.4 µm. This means that filters are now tested under conditions much more similar to real-world conditions.
Four new filter groups have been introduced: Coarse, ePM10, ePM2.5, and ePM1. The prefix “e” stands for efficiency. To be included a certain category, filters must be capable of capturing at least 50% of particulate matter corresponding to the dimensions indicated. Filters that capture less than 50% of PM10 dust are included in the Coarse group.
|Group||Class||Reference value||ΔP Final (Pa)|
|ePM1 min||ePM2,5 min||ePM10|
|0,3 ≤ x ≤ 1||0,3 ≤ x ≤ 2,5||0,3 ≤ x ≤ 10|
|ISO Coarse||–||–||< 50%||Initial gravimetric arrestance||200|
|ISO ePM10||–||–||≥ 50%||ePM10||300|
|ISO ePM2,5||–||≥ 50%||–||ePM2,5||300|
|ISO ePM1||≥ 50%||–||–||ePM1||300|