Overview
ISO 21340:2017 - "Test methods for fibrous activated carbon" - is an international standard that specifies laboratory test methods to determine the physical and adsorption properties of fibrous activated carbon (FAC). Published by ISO (Technical Committee ISO/TC 38: Textiles) in 2017 and based on JIS K 1477, the standard covers sampling guidance and procedures to measure specific surface area, pore volume, fibre and sheet properties, mass loss on drying, pH, total ash content, and adsorption performance for toluene, methylene blue, and iodine.
Key topics and requirements
- Scope & sampling
- Tests are chosen based on intended end use; samples must represent the lot and fibres are typically cut to 10 mm (or shorter) for testing.
- Water of Grade 1 quality (ISO 3696) is specified for tests where water is used.
- Physical property tests
- Determination of fibre diameter and tensile strength for single fibres.
- Tests for sheet products (non-wovens/felts and fabrics) including mass per unit area, tensile strength and elongation.
- Mass loss on drying, pH value, and total ash content procedures are specified.
- Porosity and surface
- Methods for specific surface area and pore volume determination, with apparatus, procedures and calculation instructions.
- Adsorption performance
- Procedures include breakthrough adsorption tests and equilibrium adsorption amount determinations for toluene, methylene blue, and iodine.
- Guidance on generating breakthrough curves, defining breakthrough time, and constructing adsorption isotherms.
Practical applications
- Quality control and batch verification for FAC manufacturers.
- Product specification and acceptance testing for suppliers and purchasers of filtration media, gas/vapor adsorbents, and textile-based carbon filters.
- R&D and product development to compare adsorption efficiencies (toluene, methylene blue, iodine) and optimize fibre/sheet properties.
- Environmental and occupational health testing where FAC is used for air purification, solvent recovery, or aqueous contaminant removal.
Who should use this standard
- Manufacturers of fibrous activated carbon and carbonized textile products.
- Independent testing laboratories and QA/QC teams.
- Filter and respirator designers, environmental engineers, and procurement/specification authors.
- Regulatory and certification bodies evaluating performance claims.
Related standards
Keywords: ISO 21340:2017, fibrous activated carbon, FAC test methods, specific surface area, pore volume, adsorption testing, toluene adsorption, methylene blue adsorption, iodine adsorption, fibre tensile strength, sheet properties.