Overview
ISO/TS 21083-2:2019 - Test method to measure the efficiency of air filtration media against spherical nanomaterials (size range 3 nm to 30 nm) - specifies instruments, test setup and procedures for determining the filtration efficiencies of flat sheet air filter media against airborne spherical or nearly‑spherical nanoparticles in the 3–30 nm size range. The document limits testing to spherical shapes to reduce uncertainty from particle morphology and includes examples such as silver test aerosol for solid‑phase particles.
Key topics and technical requirements
- Particle size range: Focused on nanoparticles from 3 nm to 30 nm - a critical mobility range for nanoparticle penetration.
- Test materials and aerosols: Guidance on solid‑phase aerosols (e.g., silver nanoparticles) and generation methods.
- Test setup specifications: Requirements for aerosol generation systems, tubing, Differential Electrical Mobility Classifier (DEMC), Condensation Particle Counter (CPC), neutralizers, make‑up air lines and filter mounting assemblies.
- Aerosol neutralization: Procedures and qualification of neutralizers to establish an equilibrium charge distribution (references to ISO/TS 19713-1 qualification approaches).
- Instrument qualification: CPC performance checks (flow stability, zero tests, overload), DEMC validation, leakage and uniformity checks, and counting accuracy calibration.
- Measurement procedures: Determination of correlation ratios, upstream and downstream concentration measurement (single or dual CPC options), air flow and pressure drop measurement, zero count and loading effect tests.
- Data handling: Test evaluation, reporting templates, required reporting elements, and treatment of measurement uncertainties (including reference to ISO 5725-2 statistical analysis).
- Safety and maintenance: Annexes covering instrument specs, IPA safety, radioactive device handling and routine maintenance.
Applications and who uses this standard
ISO/TS 21083-2:2019 is intended for:
- Filter manufacturers developing and certifying media for nanoparticle filtration.
- Test laboratories and QA/QC teams performing standardized efficiency measurements.
- Respiratory protection designers and PPE certifiers evaluating filtration against engineered nanoparticles.
- Environmental and occupational health researchers studying nanoparticle exposure control.
- Regulators and procurement bodies requiring harmonized test data for comparative assessment.
Practical uses include product development, performance validation, compliance testing, and comparative benchmarking of filtration media against engineered nanoparticles.
Related standards
Keywords: ISO/TS 21083-2:2019, air filtration media, nanoparticle filtration, spherical nanomaterials, 3–30 nm, filtration efficiency, aerosol generation, CPC, DEMC, neutralizer.