Filter system testing

Filter system testing

Filter analysis & air hygiene

Many work and living spaces, as well as private and public transportation systems, are equipped with air conditioning, ventilation, or air purification devices. Particularly for allergy sufferers or patients in healthcare facilities, it must be ensured that particles, pathogenic germs and allergens are retained and eliminated.

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

Stop bacteria and viruses with air filters

Wherever many people spend long periods of time together, the risk of contracting flu or cold viruses or bacteria increases. When a sick person breathes, talks, coughs or sneezes, thousands of infectious droplets – also called 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 using the Topas AFC 132 modified filter test rig developed as part of the Aeropore research project. The evaluation is performed both by particle counting to determine the amount of viruses or bacteria retained or passed through the filter in droplet form (0.2-2µm), and by microbiological methods. These are used to detect viruses and bacteria, even if they are in dry form.

The OFI offers

  • Validated tests on the retention capacity of bacteria (cocci) 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

Our services

  • Inspection of filter media for air conditioning systems in healthcare facilities (hospitals, nursing homes, etc.)
  • Determination of the separation performance of filter media with regard to airborne allergens and germs (molds, bacteria, pollen, proteins) using immunological (ELISA) and microbiological methods
  • Determination of the denaturation of allergens by direct exposure to filter systems using immunological methods
  • Identification of biomarkers using sensitive in vitro assays (expression of cell proteins), analysis and evaluation of data using mass spectrometric and bioinformatic methods.
  • Quantification and identification of particles using particle counter (2-50 μm) and SEM-EDX (≥0.5 μm)
  • Investigation of antimicrobial efficacy or resistance to microorganisms.
    • ÖNORM EN ISO 846 Determination of the effect of microorganisms on plastics
    • 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 in the use of fibers/glass fibers using in-vivo and in-vitro models
  • Certification according to ZG 210: In addition to fulfilling standardized norm tests, the air filters are put through their paces with additional scientific analyses by highly qualified experts.

OFI Expert for Medical Devices & Hygiene

DI Gabriele Ettenberger-Bornberg, BA
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