Filter analysis and air hygiene

Many working and living spaces as well as private and public transport systems are equipped with air conditioning, ventilation systems or air cleaning equipment. Especially for allergy sufferers or patients in health care facilities, it must be ensured that particles, pathogenic germs and allergens are retained and eliminated.


Safety and quality through tested filter systems

In order to permanently reduce biohazards in indoor areas, OFI experts have developed new test methods for testing (non)biological particle loads. With the evaluation of filter systems in air conditioning systems, ventilation systems or air cleaning equipment, OFI contributes to a sustainable improvement in safety and quality of life. OFI evaluates filter systems, if desired also with certificate (ZG 210) - for guaranteed safety in production, operation and at the user.


Our services

  • Determination of the retention efficiency of filter media with regard to airborne allergens and microorganisms (mould, bacteria, pollen, proteins), by means of immunological (ELISA) and microbiological methods

  • Determination of allergen denaturation due to direct effects of filter systems, by means of immunological methods

  • Identification of biomarkers by means of sensitive in-vitro assays (cell protein expression), data analysis and interpretation using mass spectrometry and bioinformatics

  • Quantification and identification of particles using a particle counter (2-50 μm) and REM-EDX (≥0,5 μm)

  • Testing of antimicrobial efficacy and resistance to microorganisms
    • ÖNORM EN ISO 846: Plastics - Evaluation of the action of microorganisms
    • ÖNORM EN ISO 20743: Textiles - Determination of antibacterial activity of textile products
    • Japanese Standards JIS Z 2801: Antimicrobial products - Test for antimicrobial activity and efficacy
    • ISO 22196 Measurement of antibacterial activity on plastic and other non-porous surfaces

  • Skin compatibility: Assessment of biocompatibility (cytotoxicity, irritation and sensitization) according to ISO 10993 and OECD Guidelines

  • Risk assessment regarding use of fibers/glass fibers using in-vivo and in-vitro models


OFI certificates for air filters

Air filters with an OFI certificate guarantee effective protection against fine particles such as pollen and allergens. To prove this excellent quality, air filters are tested with additional scientific analyses by highly qualified experts in addition to fulfilling standardised standard tests.


Stop bacteria and viruses with air filters

Wherever many people spend a long time together, the risk of contracting bacteria, flu or cold viruses increases. If a sick person breathes, talks, coughs or sneezes, thousands of infectious droplets - also known as aerosols - spread through the air.

The OFI is not only able to determine the bactericidal and virucidal activity of textiles or non-porous surfaces, but can also test the passage of bacteria and viruses through air filters (air filter testing).

The tests are carried out with the filter test rig of Topas AFC 132 modified, which was developed within the research project Aeropore. The evaluation is carried out both by particle counting to determine the amount of viruses or bacteria in droplet form (0.2-2µm) retained or passed through the filter, and by microbiological methods. These are used to detect viruses and bacteria, even if they are present in dry form.

The OFI offers

  • Validated tests on the retention capacity of bacteria (coccus) on the filter test rig
  • Validated tests on the retention capacity of viruses (bacteriophages) on the filter test rig

Determine virucidal and antimicrobial activity

  • ISO 18184 Textiles - Determination of antiviral activity of textile products
  • ISO 21702:2019 Measurement of antiviral activity on plastics and other non-porous surfaces
  • JIS Z 2801/ISO 22196 Measurement of antibacterial activity on plastics and other non-porous surfaces
  • JIS L1902/ISO 20743 Textiles - Determination of antibacterial activity of textile products


Research on filter media and particulate air pollutants

Together with its customers, OFI is researching new functional filter media to minimize particulate contamination in the air.

With the aim of reducing biological hazardous substances in indoor areas, OFI is developing a simulation system for testing filter media and investigating the influence of particulate contamination on human health as part of the FFG projects Airclean (2014-2017) and Aeropore (2017-2021). The identification of biomarkers using sensitive in-vitro assays (expression of cell proteins) and the analysis and evaluation of the data using mass spectrometric and bioinformatic methods will provide a deeper understanding of the relationship between particles and respiratory diseases.