Overview
ISO 16900-1:2019 - Respiratory protective devices - Methods of test and test equipment - Part 1: Determination of inward leakage - specifies laboratory test methods to determine inward leakage of respiratory interfaces (RI) and total inward leakage (TIL) of complete respiratory protective devices (RPD). The standard defines how to measure concentrations of specified test agents inside and outside the RPD while a human test subject performs a defined exercise regime and metabolic work rates. These controlled laboratory tests inform device performance under test conditions but do not represent actual-use performance.
Key technical topics and requirements
- Test principle: Compare concentrations of a challenge agent outside and inside the RI/RPD while a test subject performs specified exercises.
- Test agents: Three agents are specified - a gas (sulfur hexafluoride, SF6), a solid aerosol (sodium chloride, NaCl), and a liquid aerosol (corn oil). Method choices (Method 1, 2A/2B, 3) depend on device type.
- Sampling methods: Includes pulsed sampling (Method 2A) and continuous sampling (Method 2B) for NaCl; specific provisions for condensation particle counters and sampling flow rates are given.
- Human test panel: Requirements for panel selection, training, and preparation (e.g., facial hair exclusions unless manufacturer permits). The standard moved from PCA to a bivariate grid method for panel selection and adds guidance on measuring inward leakage in the ocular zone.
- Environmental and procedural limits: Ambient test conditions and tolerances (example: typical ambient range 16 °C to 32 °C and (50 ± 30) % RH), preconditioning, exercise regimes, and sample counts are defined or referenced.
- Uncertainty and reporting: Each measurement must be accompanied by an estimate of measurement uncertainty; Annex A covers application of uncertainty for compliance.
- Test equipment and RPD preparation: Details on apparatus, probe/sample tube placement, and preparation for filtering and supplied-air devices are included.
Practical applications - who uses ISO 16900-1:2019
- RPD manufacturers - to verify design, seal performance and to support conformity with performance standards.
- Test laboratories and certification bodies - to perform standardized inward leakage and TIL testing for certification and quality assurance.
- Occupational safety professionals and regulators - to interpret laboratory-based fit/leakage data when developing selection and approval policies.
- Product developers and researchers - to evaluate materials, facepiece designs, and filter/interface combinations under controlled conditions.
Related standards
Key normative references and related documents in the ISO 16900 series include:
ISO 16900-1:2019 is intended as a laboratory test-method supplement to RPD performance standards and should be used together with relevant performance and conformity documents when assessing inward leakage.