AATCC 42:2000 pdf download.Water Resistance: Impact Penetration Test
1.1 This test method is applicable to any textile fabric, which may or may not have been given a water-resistant or wa- ter-repellent finish. It measures the resis- tance of fabrics to the penetration of wa- ter by impact, and thus can be used to predict the probable resistance of fabrics to rain penetration. It is especially suit- able for measuring the penetration resis- tance of garment fabrics.
1.2 The results obtained with this test method depend on the water repellency of the fibers and yarns and on the con- struction and finish of the fabric.
2. Principle
2.1 A volume of water is allowed to spray against a taut surface of a test spec- imen backed by a weighed blotter. The blotter is then reweighed to determine water penetration and the specimen is classified accordingly.
3. Terminology
3.1 water resistance, n.—of fabric, the characteristic to resist wetting and pene- tration by water. (See also water repel- lency.)
4. Safety Precautions NOTE: These safety precautions are for information purposes only. The pre- cautions are ancillary to the testing proce- dures and are not intended to be all inclu- sive. It is the user’s responsibility to use safe and proper techniques in handling materials in this test method. Manufac- turers MUST be consulted for specific details such as material safety data sheets and other manufacturer’s recommenda- tions. All OSHA standards and rules must also be consulted and followed.
4.1 Good laboratory practices should be followed. Wear safety glasses in all laboratory areas.
7.3 Upon completion of the spraying pe- riod, the test specimen is carefully lifted, the blotter beneath removed, and then quickly reweighed to the nearest 0.1 g.
8. Evaluation
8.1 The increase in mass of the blotter in grams is calculated and the average re- sult of the three test specimens is re- ported. Individual determinations or av- erage values of over 5.0 g may be simply reported as + 5.0 g or > 5.0 g.AATCC 42 pdf download.