Overview
ISO 18695:2007 specifies the procedure for determining the resistance of textile fabrics to water penetration by low impact water spray. This international standard applies to any textile fabric, whether treated with a water-resistant or water-repellent finish or not. Primarily, ISO 18695:2007 is used to assess and predict the rain penetration resistance of apparel fabrics, especially those with medium to loose construction where more severe tests like the Bundesmann rain-shower test (ISO 9865) or Rain Test (ISO 22958) may be unsuitable.
The test evaluates how well a fabric can resist water penetration under light impact conditions, providing valuable data for manufacturers, testers, and quality controllers in the textile industry. Fabrics that do not lie flat when tensioned are excluded from this testing method.
Key Topics
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Test Principle
Water is sprayed from a specified height (610 ± 10 mm) onto a taut fabric specimen positioned above a weighed blotter. The blotter absorbs any water passing through the fabric. The increase in blotter weight after the test quantifies water penetration.
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Applicability
Suitable for medium to loosely woven textiles, whether finished or unfinished. Not recommended for highly taut fabrics or those that cannot be stretched flat under tension.
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Apparatus and Materials
Includes an impact penetration tester (Type 1 or Type 2), white textile blotting paper with defined absorbency and weight, and a laboratory balance accurate to 0.1 g. Water used is distilled or equivalent purity, maintained at 27 ± 1°C.
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Specimen Preparation and Conditioning
Test specimens of 178 mm × 330 mm are cut with warp direction lengthwise, conditioned for at least 4 hours under standard atmosphere conditions following ISO 139 before testing.
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Testing Procedure
The specimen is clamped and weighted appropriately on an inclined stand, water is sprayed for a brief interval, and the blotter is weighed pre- and post-test to measure water penetration.
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Evaluation and Reporting
The average blotter weight gain from three specimens determines the test result. Values exceeding 5.0 grams are reported as “> 5 g.” Test reports must reference ISO 18695:2007 and include sample identification, specimen count, conditioning/testing conditions, procedural deviations, and results.
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Safety Considerations
Standard laboratory safety, such as wearing safety glasses, is emphasized.
Applications
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Textile Quality Control
ISO 18695:2007 provides a method to evaluate water resistance in fabrics destined for outdoor apparel, protective clothing, and rainwear, ensuring materials meet expected performance levels.
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Product Development
Manufacturers use this standard in developing water-repellent finishes and selecting fabric constructions optimized for rain resistance without overtesting with harsher methods unsuitable for loose fabrics.
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Comparative Testing
Enables comparison between different fabric treatments, finishes, and structural designs regarding water penetration under simulated rain impact conditions.
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Research and Innovation
Facilitates the study of water repellency performance on new textile materials or finishes, enhancing innovation in the production of water-resistant textiles.
Related Standards
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ISO 9865: Textiles - Determination of water repellency by the Bundesmann rain-shower test
A more rigorous assessment designed for tightly woven fabrics.
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ISO 22958: Textiles - Water resistance - Rain tests: exposure to a horizontal water spray
Tests fabric resistance under continuous horizontal spray exposure.
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ISO 139: Textiles - Standard atmospheres for conditioning and testing
Specifies the atmospheric conditions for accurate and repeatable textile testing including water penetration tests.
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AATCC Test Method 42: Water Resistance - Impact Penetration Test
A similar method widely used in the textile industry, providing complementary test data.
ISO 18695:2007 is a crucial standard for industries aiming to measure and improve the rain penetration resistance of textiles subjected to light water impact. By following this internationally recognized methodology, manufacturers ensure product reliability and customer satisfaction in water-resistant textiles.