Air Permeability Measurement ISO 9237
topic
ISO 9237 air permeability testing clamps the fabric specimen over a circular test head of defined area, applies a standardised pressure differential across the specimen using a calibrated airflow system, and measures the volumetric flow rate of air passing through the fabric at steady state, with multiple measurements taken across the fabric width and length to account for structural variability. The test covers a wide range of fabric permeabilities through interchangeable flow measurement ranges and nozzle sizes, enabling measurement from dense filter media and windproof membranes through to open spacer fabrics and mesh constructions. Conditioning of specimens before testing is mandatory to standardise moisture content which affects inter-yarn space dimensions and therefore air flow resistance.
Role
ISO 9237 provides the internationally standardised air permeability measurement that underpins specifications in standards from outdoor sportswear to industrial filtration — its wide measurement range and simple test geometry making it the universal screening test for fabric openness across the entire spectrum of technical and apparel textile applications where airflow through the fabric structure is a functional requirement.