Overview
ISO 21683:2019 - "Pigments and extenders - Determination of experimentally simulated nano-object release from paints, varnishes and pigmented plastics" specifies a laboratory method to determine whether and how many nanoscale pigments and extenders are released from coated surfaces or pigmented plastics when mechanical stress is applied. The standard covers sample conditioning (aging, weathering), stress application (abrasion/erosion/comminution), aerosol generation and characterization, and reporting of results to support exposure and environmental assessments.
Key topics and requirements
- Scope and purpose: Experimental determination of nanoscale particle release (nano-objects) from paints, varnishes and pigmented plastics following mechanical stress. Samples are conditioned to simulate the product lifecycle.
- Stress methods: Definitions and requirements for test specimens, test apparatus and process parameters for mechanical stress (type and energy) that generate particle release.
- Measurands and metrics:
- Particle number release, area-specific and mass-specific releases
- Particle number concentration and number-weighted particle size distribution (preferred because mass-based detection is often insensitive for nanoscale particles)
- Definitions of process concentration, measuring concentration, and model room concentration
- Aerosol measurement techniques: Guidance on aerosol instrumentation such as condensation particle counters (CPC), differential electrical mobility classifiers (DEMC) and differential mobility analysing systems (DMAS), plus sampling line and aerosol conditioning requirements. Annex B provides selected measuring equipment examples.
- Preparation, procedure, calculation and reporting: Requirements for background checks, sampling interconnection, data calculation and the test report content to enable reproducibility and interpretation.
- Supporting material: Annex A includes example parameter specifications for stress methods; Annex B lists measurement equipment.
Practical applications
- Evaluate propensity of coatings and pigmented plastics to release nanoscale pigments and extenders under realistic mechanical stresses.
- Provide quantitative data for exposure assessment, risk evaluation, product stewardship and environmental impact analysis.
- Support product development (material selection, formulation changes) to minimize nano-object release.
- Serve as a reference method for certification bodies, testing laboratories, and regulatory or occupational health assessments.
Who uses this standard
- Coatings, pigment and plastics manufacturers
- Independent testing and aerosol measurement laboratories
- Regulatory agencies, occupational health & safety professionals
- Environmental scientists and product stewards conducting nano-release or lifecycle assessments
Related standards
Keywords: ISO 21683, nano-object release, paints, varnishes, pigmented plastics, aerosol measurement, particle number concentration, particle size distribution, DEMC, CPC, aging, weathering.