The filtration efficiency you need according to ISO16890

Outdoor air quality

ODA1	OUTDOOR AIR, WHICH MAY BE ONLY TEMPORARILY DUSTY Applies where the World Health Organisation WHO (2005) guidelines are fulfilled (annual mean forPM2,5 ≤ 10 μg/m3 andPM10 ≤ 20 μg/m3).
ODA2	OUTDOOR AIR WITH HIGH CONCENTRATIONS OF PARTICULATE MATTER Applies where PM concentrations exceed the WHO guidelines by a factor of up to 1,5 (annual mean for PM2,5 ≤ 15 μg/m3 and PM10 ≤ 30 μg/m3).
ODA3	OUTDOOR AIR WITH VERY HIGH CONCENTRATIONS OF PARTICULATE MATTER Applies where PM concentrations exceed the WHO guidelines by a factor of greater than 1,5 (annual mean for PM2,5 > 15 μg/m3 and PM10 > 30 μg/m3).

Supply air quality

SUP1	Applications with high hygienic demands. Examples: Hospitals, pharmaceutics, electronic and optical industry, supply air to clean rooms.
SUP2	Applications with medium hygienic demands and rooms for permanent occupation. Examples: Food and beverage production, Kindergardens, offices, hotels, residential buildings, meeting rooms, exhibition halls, conference halls, theaters, cinemas, concert halls.
SUP3	Applications with basic hygienic demands and rooms with temporary occupation. Examples: Food and beverages production with a basic hygienic demand, storage, shopping centers, washing rooms, server rooms, copier rooms.
SUP4	Applications without hygienic demands and rooms with short-term occupation. Examples: General production areas in the automotive industry, restrooms, storage rooms stairways.
SUP5	Production areas of the heavy industry and rooms without occupation. Examples: Steel mill, smelters, welding plants, garbage rooms, data centers, underground car parks.