Overview
ISO/TS 23302:2021 - Nanotechnologies - specifies requirements and recommendations for the identification of measurands that characterise nano‑objects, their agglomerates/aggregates, and materials that contain them. Published as a Technical Specification in 2021, it guides selection and reporting of measurable quantities (size, shape, chemistry, mass, density, surface properties, etc.) and provides recommendations for relevant measurement approaches across sample states (aerosols, powders, liquid dispersions, surfaces).
Key topics and requirements
- Identification of measurands: Defines what properties should be considered to characterise nano‑objects and combinations (e.g., primary particle size, hydrodynamic diameter, shape descriptors, surface composition).
- Approaches and procedure: Presents a systematic approach to determine which measurands are relevant for a given material, application or performance requirement.
- State-specific measurands: Distinguishes measurands and measurement methods by sample state - aerosols, powders, liquid dispersions, and surfaces - recognising that state affects relevant metrics.
- Measurement technique guidance: Recommends measurement techniques and links measurands to methods such as TEM, SEM, AFM, dynamic light scattering (DLS), particle tracking analysis, centrifugation, field flow fractionation, single-particle ICP‑MS, SAXS, BET, laser diffraction, XRD, XPS, Raman, FTIR and aerosol sizing/impactors.
- Chemical and surface analysis: Covers surface chemistry and bulk chemical measurands, and recommends appropriate analytical methods (XPS, XRF, EELS, SIMS, ICP techniques).
- Mass and density: Addresses measurands for particle mass and effective density and relevant aerosol and particle mass analysers.
- Reference to relevant standards: Points users to method‑specific standards and encourages conformity with existing ISO/technical standards where applicable.
Applications and who uses it
- R&D and materials development: Selecting meaningful measurands for nanomaterial design and performance testing.
- Quality control and manufacturing: Defining measurement targets for process control and lot release.
- Regulatory compliance & safety assessment: Providing consistent measurands for exposure, hazard evaluation and labeling dossiers.
- Metrology & laboratories: Guiding test method selection, reporting and inter-lab comparison.
- Standards developers & policymakers: Informing harmonised measurement frameworks and normative documents.
Related standards
ISO/TS 23302 complements and refers to a range of method‑specific standards (microscopy, spectroscopy, scattering, aerosol measurement and mass spectrometry). Users should consult the cited ISO, ASTM or other normative standards for detailed test methods and calibration requirements.
Keywords: nanotechnologies, ISO TS 23302, measurands, nano‑objects, characterization, particle size, surface chemistry, aerosols, powders, liquid dispersions, measurement methods.