Overview
EN ISO 10306:2014 - Textiles - Cotton fibres - Evaluation of maturity by the air flow method - specifies an international test method for assessing the maturity of loose, randomized cotton fibres by measuring the resistance to air flow through a packed plug of cotton under two prescribed compressions. The standard is intended primarily for cotton drawn from bales; laps, slivers or other lint sources can be tested but may give different results.
Key topics and technical requirements
- Principle: Air is passed through a specimen plug at two compressions to obtain two pressure-drop readings, PL (low compression) and PH (high compression). These values are used to calculate a maturity ratio (M) or percent maturity (P); the micronaire value is derived from PL.
- Apparatus: Required equipment includes a sensitive balance, an air-flow instrument (e.g., Fineness/Maturity Tester) with a compression cylinder (specified packing densities: ~0.1911 g/cm3 at low compression and ~0.3821 g/cm3 at high compression), air pump/valves, flow-rate control and pressure gauge.
- Specimen preparation: Samples must be well opened and randomized; blending apparatus is acceptable if it produces randomly oriented fibres (webs of parallel fibres are unsuitable).
- Conditioning and atmosphere: Samples are conditioned and tested under the standard atmosphere defined in ISO 139.
- Sampling and number of tests: Where unspecified, test at least two specimens with two tests on each; if successive PL or PH differ by more than 5% a new specimen is recommended.
- Procedure and accuracy: Record PL and PH after 10 s at each flow condition with pressure readings to 1 mm of water column. Average readings per specimen are used in calculations.
- Calibration and annexes: Annex A describes operation of the air flow instrument; Annex B describes instrument calibration and reference (international) cotton standards for calibration.
Applications and who uses it
- Quality control laboratories in ginneries, textile mills and cotton testing houses to monitor fibre maturity during raw material acceptance and process control.
- Cotton merchants and buyers assessing bale quality for trading and grading.
- Spinning and yarn manufacturers evaluating raw fibre properties that affect processing performance and end-product quality.
- Instrument manufacturers validating and calibrating air-flow maturity testers.
- Research and standards bodies studying fibre properties and comparing methods (air‑flow method vs. microscopic maturity methods).
Related standards
- ISO 139 - Standard atmospheres for conditioning and testing
- ISO 1130 - Sampling of textile fibres for testing
- ISO 2403 - Determination of micronaire value
- ISO 4912 - Microscopic method for cotton maturity
Keywords: EN ISO 10306:2014, cotton fibre maturity, air flow method, micronaire, cotton testing, textiles, Fineness/Maturity Tester, cotton fibres evaluation.