Standard Test Method for Air Permeability of Textile Fabrics

The standard test method for air permeability of textile fabrics is specified by ASTM D737. This test method provides a quick, simple, and reliable way to measure the air permeability of textile fabrics.

 

Purpose of the Test

The purpose of the test is to determine the ease with which air can pass through the fabric and to provide a measure of its breathability. It is typically performed on fabrics used for clothing, curtains, upholstery, and other similar applications [1].

 

Test Procedure

The test involves clamping a specific sample of the fabric over a circular opening in a calibrated air flow apparatus. The apparatus also includes a sample clamping device and a means of measuring air flow. The rate of air flow passing perpendicularly through a known area of fabric is adjusted to obtain a prescribed air pressure differential between the two fabric surfaces. From this rate of air flow, the air permeability of the fabric is determined. The result is expressed as the cubic feet of air per minute (CFM) that passes through a square foot of fabric [2].

Applicability

ASTM D737 applies to most fabrics, including woven fabrics, nonwoven fabrics, air bag fabrics, blankets, napped fabrics, knitted fabrics, layered fabrics, and pile fabrics. The fabrics can be untreated, heavily sized, coated, resin-treated, or otherwise treated [3].

 

Other Test Methods

For nonwoven fabrics, air permeability is also measured using the Frazier test method in accordance with standard test methods such as ASTM D737 and DIN 53887 [4].

 

Conclusion

ASTM D737 is a widely used standard test method for measuring the air permeability of textile fabrics. It provides valuable information about the breathability and air flow characteristics of fabrics used in various applications.