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5.1 This index test method indicates a unvegetated RECP’s ability to reduce rainsplash-induced erosion under bench-scale conditions. This test method may also assist in identifying physical attributes of RECPs that contribute to their erosion-control performance.5.2 This test method is bench-scale and therefore, appropriate as an index test for initial indication of product performance, for general comparison of unvegetated RECP capabilities, and for product quality assurance/conformance testing. The results of this test are not indicative of an RECP’s actual field performance.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspections/etc. Users of this standard are cautioned that compliance with Practice D3740 does not itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This index test method establishes the guidelines, requirements and procedures for evaluating the ability of unvegetated rolled erosion control products (RECPs) to protect soils from simulated rainfall (rain splash) and minimal runoff induced erosion. The critical element of this protection is the ability of the unvegetated RECP to absorb the impact force of raindrops, thereby reducing soil particle loosening through “splash” mechanisms, and limiting the ability of runoff to carry the loosened soil particles.1.2 This index test method utilizes bench-scale testing procedures and is not indicative of unvegetated RECP performance in conditions typically found in the field.NOTE 1: The values obtained with this bench scale procedure are for initial performance indication, general product comparison and conformance purposes only. These values should not be used in estimating RECP soil protection in actual field use with such calculations as the Universal Soil Loss Equation (USLE) or Revised Universal Soil Loss Equation (RUSLE) without verification from qualified, large-scale tests.1.3 This index test is not intended to replace full-scale simulation or field testing in acquisition of performance values that are required in the design of erosion control measures utilizing unvegetated RECPs.1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard.1.5.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives, and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this index test method to consider significant digits used in analytical methods for engineering design.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use and may involve use of hazardous materials, equipment, and operations. 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. Also, the user must comply with prevalent regulatory codes, such as OSHA (Occupational Health and Safety Administration) guidelines, while using the index test method.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice is meant to simulate the ability of a coating system applied to a masonry block to withstand exposure to continuous water spray (rain) and a dynamic pressure equivalent to a 98 mph wind velocity without exhibiting water leaks or weight gain, or both.1.1 This practice is for the evaluation of the ability of coatings to resist the passage of water through masonry block when exposed to water spray and air pressure.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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The coefficient of retroreflected luminance, RL, is the property of a pavement marking system that provides a measure of the retroreflective efficiency of the marking and depends on factors such as the materials used, age, and wear pattern. These conditions shall be observed and noted by the user.Under identical conditions of headlight illumination and driver's viewing, larger values of RL correspond to higher levels of visibility at corresponding geometry.The pavement marking's measured retroreflective efficiency in conditions of continuous wetting may be used to characterize the properties of the marking on the road as water is continuously falling on it. The retroreflective efficiency of the marking in conditions of continuous wetting may be different than in dry, wet or damp conditions.This test method may produce measurements of RL-Rain for pavement marking systems that do not correlate to nighttime visibility distance during typical rain events. The rainfall intensity simulated by this test method is significantly greater than most ordinary or even heavy rainfall events. As a result, the test specimen, unless it has vertical features exceeding3 mm, becomes flooded. Optics with an index of refraction less than 2.0 are practically ineffective when immersed in water. Thus, the test method is of limited applicability for assessing the wet retroreflective properties of pavement marking systems having vertical features less than 3 mm or optics having an index of refraction less than 2.0.Retroreflectivity of pavement (road) markings degrades with traffic wear and requires periodic measurement to ensure that sufficient line visibility is provided to drivers.Newly installed pavement markings may have a natural surface tension or release agents which prevent wetting of the marking by rain/water. This phenomenon produces unreliable and unrepeatable results when measuring retroreflective efficiency under wet conditions. This non-wetting phenomenon is generally eliminated after one month of wear and weathering on the road. A wetting agent can be used to estimate the RL-Rain properties of new markings (see 5.4).Roadway characteristics such as longitudinal slope, cross slope and pavement porosity will impact the results of this test method.1.1 This test method covers a measurement of the wet retroreflective (RL-Rain) properties of horizontal pavement marking materials, such as traffic stripes and road surface symbols.1.2 This method of measuring wet retroreflective properties (RL) of pavement markings utilizes a method of continuously wetting the marking during measurement (see Fig. 1).Note 1—Test Method E 2177 may be used to describe the retroreflective properties of pavement markings in conditions of wetness after a period of rain.1.3 This test method is most suitable for laboratory use under controlled conditions, but may also be used for field measurements when the necessary controls and precautions are followed.1.4 This test method specifies the use of reflectometers that can measure pavement markings per Test Method E 1710. The entrance and observation angles required of the retroreflectometer in this test method are commonly referred to as “30 meter geometry.”1.5 This test method has been shown to produce reasonable results for pavement marking systems with optics having an index of refraction greater than 2.0 and structured markings having vertical structures greater than or equal to 3 mm. Users should exercise caution when using this test method for pavement marking systems with optics having an index of refraction less than 2.0 or markings having vertical structures less than 3 mm.1.6 Results obtained using this test method should not be the sole basis for specifying and assessing the wet retroreflective effectiveness of pavement marking systems. Users should complement the results of this test method with other evaluation results, such as nighttime visual inspections.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. 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.Note 2—An alternative test method designed to better represent the retroreflective efficiency of pavement marking systems under typical rain events is under development.FIG. 1 Illustration of Measurement

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