Overview
CEN ISO/TS 21083-2:2019 - "Test method to measure the efficiency of air filtration media against spherical nanomaterials - Part 2: Size range from 3 nm to 30 nm" specifies a laboratory test method for quantifying filtration efficiency of flat sheet air filtration media against airborne nanoparticles (3 nm–30 nm). The Technical Specification focuses on spherical or nearly-spherical particles to reduce uncertainties caused by particle shape and defines the required instruments, test setup and procedures for reliable, repeatable measurements.
Key topics and technical requirements
- Scope: Measurement of filtration efficiency of flat sheet filter media for particles sized 3 nm to 30 nm; limited to spherical particles.
- Test materials: Examples include solid-phase aerosols (e.g., silver nanoparticles); methods for aerosol generation are described.
- Test setup and instrumentation: Detailed specification and qualification of test rig components, including aerosol generation systems, tubing, neutralization, test filter mounting, and measurement instruments such as CPC (Condensation Particle Counter) and DEMC.
- Aerosol neutralization: Procedures to achieve an equilibrium charge distribution and qualification of neutralizers to control particle charge state.
- Qualification and calibration: Rig qualification tests for CPCs and DEMC, leak checks, uniformity of test aerosol concentration, and counting accuracy calibration.
- Test procedures: Stepwise protocol covering preparatory checks, equipment preparation, airflow and pressure-drop measurements, zero-count and leakage tests, loading effect tests, and measurement protocols for upstream/downstream concentrations (single or dual CPC arrangements).
- Data handling: Test evaluation, measurement uncertainties, reporting requirements and required reporting elements are defined to support consistent, transparent results.
Applications
- Product development and quality control for air filter manufacturers evaluating nanofiltration performance.
- Independent test laboratories performing standardized filtration efficiency testing for regulatory compliance or comparative certification.
- Research groups studying nanoparticle filtration, aerosol science, and material performance in the ultrafine range.
- HVAC, cleanroom, pharmaceutical and occupational health stakeholders assessing filters or PPE against engineered nanomaterials and ultrafine particulate risk.
Who should use this standard
- Filter and media manufacturers
- Accredited testing laboratories and certification bodies
- R&D teams in aerosol filtration and nanomaterials
- HVAC engineers, cleanroom validation specialists, and occupational safety professionals
Related standards
- ISO/TS 19713-1 (neutralization qualification referenced in the document)
- ISO 29461-1 (filter medium neutralization procedures referenced)
- Other ISO/CEN standards on aerosol measurement, filter testing and particle counting
Using CEN ISO/TS 21083-2:2019 helps ensure consistent, traceable measurement of nanometer-scale filtration efficiency for spherical particles, improving comparability across labs and supporting product claims for ultrafine particle capture.
