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Filter classes

Tips for selecting filters

HVAC – heating, ventilation, air conditioning

A modern ventilation system not only ensures a healthy indoor climate, but also saves enormously on energy costs. Advanced air filter systems are already standard in modern residential and commercial spaces. In addition, room air filters are becoming increasingly important due to high production requirements in industry. To ensure hygienic operation of the ventilation technology, the filters must be changed regularly. But which room air filter is suitable for which purpose? What filter classes are there? We give you tips on choosing your air filters.

What filter classes are there?

When it comes to particle filters for ventilation systems, a general distinction is made between coarse dust filters, fine dust filters and suspended matter filters. The name of the filter depends on the size of the dust grain that can be filtered, which is given in micrometers (µm). 1 µm corresponds to 1/1000 mm. Coarse dust filters separate particles that are larger than 10 μm. Fine dust filters filter particles between 1 and 10 μm in size. Suspended particle filters are used to separate particles that are smaller than 1 μm. Coarse dust filters and fine dust filters are installed in accordance with the DIN EN ISO 16890 (DIN EN 779) divided into different classes. The HEPA filters are classified according to the DIN EN 1822 and DIN EN ISO 29463.

  • Coarse dust filter: Separation of particles with a size of > 10 μm. Coarse dust filters are usually used as pre-filters. A distinction is made between classes G1 to G4.
  • Fine dust filter: Separation of particles with a size of 1 to 10 μm. Fine dust filters are available in filter classes M5, M6, F7, F8 and F9. Their filtration ranges from medium-sized dust (M5 and M6, formerly F5 and F6) to fine dust (F7-F9).
  • HEPA filter: Deposition of particles < 1 μm
Filter classes
Filter classes Filter classes

Which filter classes are available at BRANOfilter?

BRANOfilter offers versatile solutions for all classes of fine dust filters and coarse dust filters. You will receive from us Panel filterFilter matsZ-line filterCompact filter and special filters. You can use our filters for air conditioning systems with and without heat recovery. Our products fit into the devices of all common manufacturers. The same applies to systems for forced ventilation in low-energy houses and for controlled living space ventilation (KWL).

Which filter classes are used in air conditioning systems?

For common air conditioning systems (RLT systems), coarse dust filters and fine dust filters are used in particular, often in combination. Analogous to the guidelines for indoor air technology and indoor air quality, VDI 6022, we recommend at least a filter of filter class F7 for filtering outside air. Depending on the outside air quality, several filter levels are advisable. To filter circulating air or secondary air, you should use at least a class M5 filter. Filtering the exhaust air protects your device from dust, mites and dirt particles from inside the room and ensures a longer service life for the system, possibly in conjunction with more efficient heat recovery. When cleaning mixed air, i.e. a mixture of outside air and part of the exhaust air (recirculated air), at least a filter of filter class F7 is also advisable.

If air quality requirements are low, a lower filter class may be sufficient. Do you have any questions about selecting the appropriate filter class? We are happy to help.

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We are here to help you. Whether you have questions, are looking for tailor-made solutions or simply want initial advice. Do not hesitate to contact us.

Your concerns are important to us. We look forward to hearing from you and are happy to assist you.

BRANOfilter GmbH

Industriestraße 23

90599 Dietenhofen


Phone: +49 9824 955 0


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