The wide range of filter elements regarding size, design and efficiency, challenges manufacturers during quality control. Various standards lay out different test instrumentation to measure the efficiency of diverse filters and filter materials for distinct applications. Efficiency is commonly tested by particle size as outlined in ISO 11155-1 and DIN EN 71460 -1+3 for cabin air filtration, ISO 29463 for HEPA/ULPA filtration, and ISO 16890 for general ventilation filtration.
These measurements are paired with determining the pressure loss at a rated airflow. Integrating the requirements of these standards into one system embodies the challenge of efficiency testing from ePM10 up to H14. Each standard provides details of the duct design, typically 610 mm x 610 mm (300 mm x 600 mm for cabin air), and the necessary instrumentation for test aerosol generation and measurements. With over 40 years in filter testing and aerosol measurement, Palas consistently rolls out top-tier test rigs that meet varied requirements.
Dual-channel system with aerosol generation and measurement, U-SMPS and Promo LED 2300 for efficiency testing from 0.02 µm to 10 µm.
THE TEST DUCT
The FET System enables defined testing of filter elements from 100 x 100 mm up to 610 x 610 mm. Accurate and internationally comparable testing demands the test channels’ adaption concerning flow guidance and aerosol distribution to the size of filter elements. It is also available as a dual channel system for diverse testing purposes.
A design encompassing three duct sizes ensures optimal flow conditions. The vertical orientation of these channels perfects aerosol transport for coarse particles up to 10 µm as needed for ISO 16890. The aerosol instrumentation, such as aerosol generation and measurement, can be used in each duct. It is essential that the integrated components are selected based on the corresponding airflow and the efficiency requirements ranging from 0% to 99.995%.
Palas® FET Dual Channel Air Filter Element Filtration Performance Test Rig
AEROSOL GENERATION
The foundation of aerosol generation is laid out in VDI 3491. A test aerosol should maintain constancy in particle size and concentration. The FET System can be armed with up to five different generators. Palas showcases over 18 distinct aerosol generation systems, with variants for different concentrations and material as DEHS, PaO, NaCl, KCl, and solid powders to cover particle sizes from 5 nm up to 200 µm.
AEROSOL MEASUREMENT FROM 5 NM UP TO 40 µM
All equipment comes from a single supplier – Palas. Aerosol spectrometers are available for a wide size range. Precision and userfriendly operation are standards of the measurement technology within the FET Systems.
CONCLUSION
Filter testing demands international comparability to standardized filter tests. Depending on client needs, individual test channels are designed that encapsulate requirements from multiple filter testing standards: ISO 29463-5 for HEPA/ULPA filter elements; ISO 16890 for room air filters; ISO 11155-1 and DIN 71460-1/-3 for automotive cabin air filters.
As an addition to ensure filter quality, ISO 29463-1 requires that all HEPA/ULPA filters with an efficiency of 99.95% or higher (ISO 35H/H13) be tested for local efficiency according to ISO 29463-4 and overall efficiency according to ISO 29463-5. In addition to bolstering filter quality, ISO 29463-1 mandates that all HEPA/ULPA filters with an efficiency of 99.95% or higher undergo specific tests.
Test requirements for different standards
Palas® regularly conducts webinars on a variety of topics to pass on its expertise in aerosol measurement technology, which are presented in detail online by Palas® technical experts and industry scholars from around the world. Register for the webinar and get the information as soon as possible!
Topic: Ensure the quality and development of your products with the FET System (English)
Time: Thursday, January 18, 2024 16: 30 – 17: 30
Speaker: Martin Schmidt / Head of Division Industry & Science