Air permeability is the property of a fabric to allow passage of air through it under the effect of a difference in pressure across its two faces. It is defined as the volume of air passing through a defined area under a specified pressure difference over a known period of time. It is a very important property for fabrics which are used under conditions where it is necessary to know precisely the amount of air passing through it.
|Test area||4 and 10 cm�|
|Rotameters||9 to 90; 65 to 650; 360 to 3,600; and 1,940 to 19,400 Iph at NTP (accuracy � 3% of FSR in each range) range is optional.|
|Pressure indicator||Electronic type with a pressure transducer and digital display to measure and indicate pressure upto 10 inch mm water column (least count 0.1)|
|IS 11056-1984 DIN 53887||Method for Determination of Air Permeability of Fabrics Testing of Textiles - Determination of the Air Permeability of Fabrics|