【国外标准】 Standard Specification for Color and Appearance Retention of Variegated Color Plastic Siding Products (Withdrawn 2018)

This specification establishes requirements and test methods for the color and appearance retention of variegated color plastic siding products. Color retention testing provides a method for estimating the acceptability of color change in a siding product over a period of years of service. Characterization of color and appearance for variegated colors is complicated by the presence of multiple colors in a random pattern. The procedure is based on using a template to reference 6 spots for color measurement. The color region for a color is determined by measuring the Hunter L, a, b color values for a sample population and calculating the average Hunter L, a, b color value. Ellipsoid Value Equations are used to determine the ellipsoid value representing the change in color due to weathering. Samples shall be exposed at three test sites: Temperate Northern represented by a site located in Louisville, KY or Cleveland, OH; hot, humid represented by a site located in Miami, FL, and hot, dry represented by a site located in Phoenix, Arizona. Materials shall be tested and the individual grades shall conform to specified values of ellipsoid value, color retention, and variegation change.1.1 This specification establishes requirements and test methods for the color and appearance retention of variegated color plastic siding products.1.2 Color retention testing provides a method for estimating the acceptability of color change in a siding product over a period of years of service.1.3 Characterization of color and appearance for variegated colors is complicated by the presence of multiple colors in a random pattern. The procedure is based on using a template to reference six spots for color measurement.1.4 Methods of indicating compliance with this specification are provided.1.5 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 1—There is no known ISO equivalent to this standard.