Overview
EN ISO 29463-3:2018 (ISO 29463-3:2011) specifies the test procedure for determining the particle-removal efficiency of flat sheet filter media used in high-efficiency filters (HEPA/ULPA). Endorsed by CEN in 2018 and derived from ISO 29463-3:2011, this part of the ISO 29463 series defines particle-counting based test methods and measurement requirements for flat media when used together with ISO 29463-1, -2, -4 and -5.
Key topics and technical requirements
- Test principle: Efficiency is measured by a particle-counting method using either mono-disperse or poly-disperse test aerosols; sampling is performed upstream and downstream of the media.
- Test apparatus & arrangements: Detailed requirements for aerosol generation, conditioning (e.g., solvent vaporization), neutralization, mixing with filtered test air, and sampling hardware.
- Sampling and specimen preparation: Procedures for sampling sheet media and mounting specimens in a test filter assembly.
- Face velocity & pressure drop: Determination of filter medium face velocity and measurement of differential pressure at prescribed velocities.
- Penetration and efficiency calculations: Defined symbols, units and equations to calculate particle concentrations, penetration, mean penetration and mean efficiency (including statistical upper/lower 95% confidence limits).
- Mono- vs poly-disperse methods: Guidance on test arrangements and particle counters appropriate to each aerosol type.
- Production and physical tests: Annexes and clauses for production testing (e.g., production-line penetration checks), differential pressure measurement and physical property testing of media.
- Documentation & maintenance: Requirements for test reports, routine maintenance and inspection of test apparatus.
Applications and users
EN ISO 29463-3:2018 is used by:
- Filter manufacturers validating flat sheet HEPA/ULPA media performance.
- Test laboratories conducting standardized efficiency and penetration testing using particle counting.
- Specifiers and purchasers (pharma, semiconductor, healthcare, cleanrooms, HVAC) requiring verified media performance for critical environments.
- Quality and R&D teams developing or qualifying new filter media formulations or production processes.
Practical applications include performance certification of filter media, production line quality control, comparative evaluation of media types, and establishing baseline pressure-drop vs efficiency characteristics for cleanroom and critical ventilation systems.
Related standards
- ISO 29463-1 - Classification, performance, testing and marking
- ISO 29463-2 - Aerosol production, measuring equipment, particle-counting statistics
- ISO 29463-4 - Leak test (scan method)
- ISO 29463-5 - Test methods for filter elements
- Supersedes: EN 1822-3:2009
Keywords: EN ISO 29463-3:2018, ISO 29463-3, high-efficiency filters, filter media, testing flat sheet filter media, particle counting, HEPA, aerosol generator, penetration, face velocity, pressure drop.