Overview
ISO 29463-5:2022 - "High-efficiency filters and filter media for removing particles in air - Part 5: Test method for filter elements" - defines standardized test methods to determine filter element efficiency at the most penetrating particle size (MPPS). It is part of the ISO 29463 series (derived from EN 1822) and is intended to be used alongside ISO 29463‑1, ‑2, ‑3 and ‑4. The standard covers test apparatus, aerosol generation, particle-counting methods, test procedures, evaluation and reporting for HEPA/ULPA and related high‑efficiency filters.
Key topics and requirements
- MPPS-based efficiency testing: Efficiency is assessed at the MPPS (the particle size where penetration is highest); for many micro‑glass media MPPS is typically 0.12–0.25 μm. Annex B provides guidance for filters with MPPS ≤ 0.1 μm (e.g., membrane media).
- Test methods: Supports testing with mono‑disperse and poly‑disperse aerosols; allows particle counting with instruments such as OPC, CPC, or particle sizing systems (e.g., DMPS) where appropriate.
- Test rig and sampling: Defines test duct layout, air conditioning, aerosol mixing, filter mounting, pressure‑drop measurement and sampling locations to ensure representative upstream/downstream particle counts.
- Alternate and statistical methods: Includes alternate scan or statistical methods for specific filter groups (e.g., alternate method for groups H and U; statistical method for group E low‑efficiency filters).
- Charged fibre media: Annex C provides normative procedures and classification guidance for filters using media with (charged) synthetic fibres.
- Test documentation and maintenance: Specifies required test report content and maintenance/inspection of test apparatus to ensure repeatability and traceability.
Applications and users
ISO 29463-5 is used by:
- Filter manufacturers for product qualification and classification (HEPA/ULPA performance).
- Independent test laboratories performing standardized efficiency and leakage testing.
- HVAC and cleanroom engineers specifying filters for controlled environments (pharma, semiconductor, healthcare).
- Facility managers and procurement teams requiring verifiable filter performance data.
- Regulators and conformity assessors referencing standardized test results for compliance.
Practical benefits include reproducible, particle‑count‑based efficiency data at the MPPS, improved comparability between products, and methods tailored for advanced media (membranes, charged fibres).
Related standards
Keywords: ISO 29463-5, HEPA testing, ULPA, MPPS, filter efficiency test, aerosol generation, particle counting, charged fibres, filter media.