Rain test

Water resistance test methods include AATCC 127 (hydrostatic pressure test), AATCC 42 (impact penetration test), and AATCC 35 (rain test). In the hydrostatic pressure test, a sample is subjected to a column of increasing water pressure until leakage occurs. The impact penetration test requires water to be sprayed on the taut surface of a fabric sample from a height of two feet. The fabric is backed by a blotter of predeterrnined weight, which is reweighed after water penetration. The rain test is similar in principle to the impact penetration test. 

Rain-resistant fabrics protect against water penetration during a rain of moderate intensity and pass AATCC Test Methods 22 and 35 (Rain Test). 

The rain test simulates the effects of rainfaU the hydrostatic head on the spray controls the intensity of spraying. The repeUency is rated by the weight of water that penetrates the fabric and is absorbed by a blotter mounted behind the fabric at a specific intensity of spraying (AATCC Test Methods 35 and 42 INDA Standard Test 80.2-92). 

Military Standard. "Fuze and Fuze Components, Environmental and Performance Tests for MIL-STD-331 (1966 1967) Class 100. Laboratory Tests - Jolt (101) Jumble (102) Forty-Foot Drop (103) Transportation Vibration (104) Temperature Humidity (105) Vacuum Steam Pressure (106) Salt Spray (Fog) (107) Waterproofness (108) Rain Test (Exposed Fuze Storage) (109) Fungus Resistance (110) Five-Foot Drop (111) Extreme Temperature Storage (112) Thermal Shock (113) Rough Handling (Packaged)... 

Rain Test (Exposed Fuze Storage) Test 109 is briefly described in Vol 4, p D1096-L... 

Fig. 7.9. Efficiency data for two test cells (active area 4 cm2) exposed to outdoor conditions for 1 year. The efficiencies of the cells were measured from time to time with an indoor solar simulator. The dye used is Ru(NCS)2(2,2 -bipyridyl-4,4 -dicarboxylate)2 (N719). 0.6 M hexylmethylimidazolium iodide (HMII), 0.1 M Lil, 0.05 M I2, 0.5 M tert-butylpyridin (TBP) in propionitril was used as the electrolyte. Surlyn 1702 (Dupont) was used as the sealant. The cells were placed under a window to protect them from rain. Test location INAP, Gelsenkirchen, Germany...

AATCC Test Method 35-2000, Water resistance rain test . Technical Manual of the American Association of Textile Chemists and Colorists, Research Triangle Park, American Association of Textile Chemists and Colorists, 2003, 85-86. 

Roth, R., Blanchard, C., Harte, J., Michaels, H., and El-Ashry, M. T. (1985) The American West s Acid Rain Test, World Resources Institute, Washington, DC. 

The fabric s resistance to penetration and absorption of water can be measured by two different kinds of tests simulated rain tests and penetration pressure tests. 

The Bundesmann rain tester was developed in 1935 and is similar to the rain test suggested by AATCC Test Method 35, but the method of estimating the water penetration through the fabric is different. Bundesmann rain tester measures the water collected in the cups covered with test fabric and subjected to simulated rainfall, whereas the AATCC Test Method 35 measures the change in the weight of blotter paper placed under the fabric subjected to simulated rain. 

AATCC test method 35-1980. Water resistance rain test. AATCC technical manual. vol. 82. 2007. 

The rain test is used to evaluate the water tightness of various closures and cabinets. For this test the top and all sides of closures are exposed to continuous water spray for 1 h at an operating pressure of 0.352 kg/cm. The test is described in detail and the pass/fail criteria are given in UL 497 [12]. 

Protectors for Paired Communications Circuits, Rain Test, UL 497, 1992. 

Rain Penetration. The degree to which rain penetrates brickwork greatly affects the thermal insulation value and the resistance to frost damage. It depends on the integrity of the structure, the workmanship, as well as the porosity of the bricks and mortar. It is influenced by wind conditions and site exposure to driving rain. Test cabinets with water... 

Penetration by Water (Rain Test) for Nonwoven Fabrics (NWSP 080.2.R0 (15))... 

The AATCC 35-1994 rain test developed by Slowinske and Pope [156] simulates exposure to rain of variable intensity (Fig. 12.7). A sample of the fabric backed by a weighed paper blotter is sprayed with water for 5 min. The blotter is weighed to determine the amount of water that has leaked through the fabric. The hydrostatic pressure of water and, consequently, the intensity of the impact of its drops on the fabric is varied in increments of 0.3 m (1 ft) from 0.6 m to 2.4 m (2 ft to 4 ft). The rain test has ranked fabrics in the same order as exposure to a 3-in. rain, but some discrepancies became evident in the correlation with l-in./h rain. 

Nevertheless, Slowinske and Pope concluded that the rain test correlated with the exposure to rain (simulated in a rain room) better than any other test. 

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