NEW STANDARD FOR AIR FILTERS
The EN 779 standard will be canceled completely mid of 2018, and ISO 16890 will be used as a new standard for Air Filter. The main change in standard allows the user to make the filter choice much more precise according to the needs of the users.
Healt Effects Of Particulate Matter
Due to increased air pollution, the effects of particulates on human health has begun to be discussed in more detail. The results show that fine dusts are a serious health hazard that causes respiratory diseases and cancers.
Air filters for general ventilation are widely used in buildings for heating, ventilation and air conditioning applications. Air filters increase the indoor air quality by reducing the particulate matter concentration, thereby protecting human health considerably.
Particles larger than 10 μm in the atmosphere collapse very quickly and they can only hang in the air in strong wind near the source they are leaving. As an exception, some light fibers can stay in the air longer, despite their large diameter. Most particles larger than 10 μm in diameter can be seen with the naked eye in case of proper illumination and contrast. Under normal conditions, the minimum visible particle diameter is 30 μm and above.
Particles ranging in diameter from 5 to 10 μm or larger are separated and trapped by the upper respiratory tract. The intermediate sizes collaps on air channels of the lungs, then swallowed or coughed. Particles ranging in diameter from 2.5 to 5 μm are likely to be retained in human lungs and are returned to the upper respiratory tract without falling into the depths of the lungs.
Particles ranging in diameter from 1 to 2.5 μm are retained in the bronchi and pose risks to human health.
The particles at 1 μm and below are small enough to interfere with the blood flow from the cell membranes of the alveoli.
Why Has ISO 16890 Been Launched Instead of EN779:2012
A synthetic powder called ASHRAE dust is used in the efficiency test of an air filter according to EN779: 2012 standard. The test is done by loading the filter with this powder in the laboratory environment. By this way, the efficiency of the filter can be calculated in the particle size of only 0.4 μm .
In operating conditions, filters are exposed to pollutants with a variety of different sized particulate. Therefore, the data obtained in the laboratory is insufficient to determine the performance of an air filter.
The EN 779: 2012 standard which is used in the classification of Coarse filters, Medium Filters and Fine Filters will be replaced by the ISO 16890 standard with an 18-month transition period. With this change in standard, filter users will be able to choose the filter much more accurate according to their needs.
ISO 16890 standard considers for the particle size (Particulate Matter = PM) between 0.3 μm and 10 μm for efficiency evaluation.
About Filter Media
The EN 779: 2012 standard has minimum efficiency values to be provided for F7, F8 and F9 filters. This is mainly because the synthetic fiber filter media shows very low efficiency in tests after removal of the electrostatic filtering effect with isopropanol. This is also the most important reason for recommending filters to the end users with glass fiber media instead of bag filters with synthetic fiber media. In addition to the ISO 16890 standard, the minimum efficiency value stands out as a more restrictive step. This situation; will help to replace bag filter produced with glass fiber media instead of the bag filter produced with synthetic fiber media.