What is ASTM D737?
ASTM D737 is a test standard that specifies the method for measuring the air permeability of textile fabrics.
The test method described in ASTM D737 provides a quick, simple and reliable method for determining the air permeability of textile fabrics.
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. The test is typically performed on fabrics used for clothing, curtains, upholstery and other similar applications.
The testing equipment for ASTM D737 typically consists of a calibrated air flow apparatus, a sample clamping device and a means of measuring air flow. The test involves clamping a test specific of the fabric over a circular opening in the apparatus and measuring the rate of air flow through the fabric.
The result is expressed as the cubic feet of air per minute (CFM) that passes through a square foot of fabric.
The air permeability of the fabric is determined by comparing the test results to a standard reference fabric or by conducting multiple tests under different pressure conditions.
Basic steps of ASTM D737 air permeability testing
1
Preparation
The fabric sample is cut to a specific size and conditioned in a controlled environment.
2
Clamping
The fabric sample is clamped securely to the test apparatus.
3
Pressure differential
A pressure differential is created across the fabric sample by flowing air through it.
4
Air flow measurement
The air flow through the fabric sample is measured using a flow meter or other suitable device.
5
Calculating air permeability
The air permeability is calculated from the measured air flow and the pressure differential across the sample.
6
Reporting results
The results are reported in units of cubic feet per minute per square foot (cfm/ft2). The test is typically repeated several times to obtain an average result for the sample.
Test Types
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