Overview
EN ISO 21083-1:2018 (ISO 21083-1:2018) defines a laboratory test method for determining the fractional filtration efficiency of flat-sheet air filtration media against spherical or nearly‑spherical nanoparticles in the 20 nm to 500 nm size range. The standard specifies the required test instruments, rig setup and the step‑by‑step procedure to measure upstream and downstream particle concentrations while limiting shape‑related uncertainties by using spherical test aerosols.
Key topics and technical requirements
- Scope and principle: Method for flat sheet filter media using airborne spherical nanoparticles (20–500 nm).
- Test aerosols: Includes guidance for liquid‑phase aerosols such as DEHS and methods for aerosol generation and drying.
- Test rig components: Detailed specifications for aerosol generator, tubing, dryer, DEMC, neutralizer, make‑up air line, test filter mounting, and CPC (condensation particle counter) downstream/upstream sampling.
- Qualification and calibration: Procedures to qualify the test apparatus (CPC tests, DEMC tests), aerosol neutralizer performance, and counting accuracy.
- Measurement procedure: Preparatory checks, generator and neutralizer operation, filter medium neutralization, airflow and pressure‑drop measurement, zero‑count and leakage checks, loading effect tests and data collection protocols.
- Data evaluation and reporting: Calculation of fractional efficiencies, uncertainty assessment and required reporting elements.
- Measurement uncertainty & maintenance: Guidance on estimating uncertainties and routine maintenance items to ensure repeatability.
Practical applications and users
This standard is designed for professionals who need robust, repeatable nanoparticle filtration data, including:
- Filter media manufacturers validating product performance against nanoparticles.
- Independent testing and certification laboratories performing efficiency measurements for product claims and regulatory compliance.
- HVAC and cleanroom engineers assessing media suitability for environments sensitive to ultrafine particles.
- Personal protective equipment (PPE) developers evaluating filter layers for respirators and masks.
- Research institutions studying filtration mechanisms and nanoparticle capture at the nanoscale.
Using this standard improves comparability of test results, supports product development, and helps demonstrate conformity to industry specifications for nanoscale air filtration.
Related standards
- ISO 29461‑1 (filter medium neutralization procedures referenced in test steps)
- ISO/TS 19713‑1 (aerosol neutralizer qualification methods)
Keywords: ISO 21083-1, EN ISO 21083-1:2018, air filtration media, nanoparticle filtration, filtration efficiency, DEHS aerosol, CPC, aerosol generation, nanoscale filters.