More D Comparative tests as directed in 5. Statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of fabric of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing.
|Published (Last):||2 October 2010|
|PDF File Size:||2.56 Mb|
|ePub File Size:||15.61 Mb|
|Price:||Free* [*Free Regsitration Required]|
Document Center Inc. The fabrics may be untreated, heavily sized, coated, resin-treated, or otherwise treated. Instructions are provided for testing specimens with, or without, wetting. It is not suited for the course direction of warp knit fabrics or either direction of most other knitted fabrics. The U. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Significance and Use This test method for the determination of tearing strength by the falling pendulum type apparatus is used in the trade for the acceptance testing of commercial shipments of fabrics, but caution is advised since technicians may fail to get good agreement between results on certain fabrics.
Comparative tests as directed in 5. In case of a dispute arising from differences in reported test results when using this test method for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories. Statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of fabric of the type in question.
The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using appropriate statistical analysis and an acceptable probability level chosen by the two parties before the testing began.
If a bias is found, either its cause must be found and corrected or the purchaser and the supplier must agree to interpret future test results with consideration to the known bias. Microprocessor systems for automatic collection of data can provide economical and reliable results when properly calibrated.
See Test Methods D and D
ASTM D1424 - Elmendorf Tear