ASTM E903-12
Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres

Standard No.

ASTM E903-12

Release Date

2012

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E903-20

Latest

ASTM E903-20

Scope

5. Significance and UseTop Bottom

5.1 Solar-energy absorptance, reflectance, and transmittance are important in the performance of all solar energy systems ranging from passive building systems to central receiver power systems. This test method provides a means for determining these values under fixed conditions that represent an average that would be encountered during use of a system in the temperate zone.

5.2 Solar-energy absorptance, reflectance, and transmittance are important for thermal control of spacecraft and the solar power of extraterrestrial systems. This test method also provides a means for determining these values for extraterrestrial conditions.

5.3 This test method is designed to provide reproducible data appropriate for comparison of results among laboratories or at different times by the same laboratory and for comparison of data obtained on different materials.

5.4 This test method has been found practical for smooth materials having both specular and diffuse optical properties. Materials that are textured, inhomogeneous, patterned, or corrugated require special consideration.

5.4.1 Surface roughness may be introduced by physical or chemical processes, such as pressing, rolling, etching, or deposition of films or chemical layers on materials, resulting in textured surfaces.

5.4.2 The magnitude of surface roughness with respect to the components of the spectrophotometer and attachments (light beam sizes, sphere apertures, sample holder configuration) can significantly affect the accuracy of measurements using this test method.

5.4.3 Even if the repeatability, or precision of the measurement of textured materials is good, including repeated measurements at various locations within or orientations of the sample, the different characteristics of different spectrophotometers in different laboratories may result in significant differences in measurement results.

5.4.4 In the context of 5.4.3, the term 憇ignificant?means differences exceeding the calibration or measurement uncertainty, or both, established for the spectrophotometers involved, through measurement of or calibration with standard reference materials.

5.4.5 The caveats of 5.4.3 and 5.4.4 apply as well to measurement of smooth inhomogeneous or diffusing materials, where incident light may propogate to the edge of the test material and be 憀ost?with respect to the measurement.

5.5 This test method describes measurements accomplished over wider spectral ranges than the Photopic response of the human eye. Measurements are typically made indoors using light sources other than natural sunlight, though it is possible to configure system......<......

ASTM E903-12 Referenced Document

• ASTM E1084 Standard Test Method for Solar Transmittance (Terrestrial) of Sheet Materials Using Sunlight
• ASTM E1175 Standard Test Method for Determining Solar or Photopic Reflectance, Transmittance, and Absorptance of Materials Using a Large Diameter Integrating Sphere
• ASTM E2554 Standard Practice for Estimating and Monitoring the Uncertainty of Test Results of a Test Method Using Control Chart Techniques
• ASTM E275 Standard Practice for Describing and Measuring Performance of Ultraviolet, Visible, and Near-Infrared Spectrophotometers
• ASTM E424 Standard Test Methods for Solar Energy Transmittance and Reflectance (Terrestrial) of Sheet Materials
• ASTM E490 Standard Solar Constant and Zero Air Mass Solar Spectral Irradiance Tables
• ASTM E772 Standard Terminology Relating to Solar Energy Conversion
• ASTM E971 Standard Practice for Calculation of Photometric Transmittance and Reflectance of Materials to Solar Radiation
• ASTM G173 Standard Tables for Reference Solar Spectral Irradiances: Direct Normal and Hemispherical on 37° Tilted Surface
• ASTM G197 Standard Table for Reference Solar Spectral Distributions: Direct and Diffuse on 20° Tilted and Vertical Surfaces

ASTM E903-12 history

• 2020 ASTM E903-20 Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres
• 2012 ASTM E903-12 Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres
• 1996 ASTM E903-96 Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres