ASTM C1549 is the standard for determining solar reflectance near ambient temperature using a portable solar reflectometer. It provides a practical method for measuring how much solar energy a surface reflects under conditions close to normal service temperature, which can help support product comparison, performance evaluation, and specification work. For materials and assemblies where solar reflectance matters, this standard offers a consistent technical basis for testing and reporting results.

What is ASTM C1549?

This standard, titled Standard Test Method for Determination of Solar Reflectance Near Ambient Temperature Using a Portable Solar Reflectometer, describes a test method for evaluating solar reflectance with portable equipment. In practical terms, ASTM C1549 is intended to help users measure reflective performance near ambient temperature in a repeatable way. It is commonly used when a quick, field-friendly or on-site measurement approach is needed for product assessment, quality control, or documentation.

Where is ASTM C1549 used?

ASTM C1549 is commonly used in settings where solar reflectance measurements are needed for roofing materials, coatings, and other exposed surfaces. It may support work in product testing, field inspection, and procurement verification when reflective performance is part of the specification. Because the method uses a portable solar reflectometer, it is well suited to situations where testing must be performed directly on installed or finished materials without extensive sample preparation.

Why is ASTM C1549 important?

This standard matters because it helps make solar reflectance measurements more consistent and comparable across different tests and products. ASTM C1549 can support compliance efforts, reduce uncertainty in material evaluation, and provide a clear basis for quality control decisions. For buyers, specifiers, and testing teams, it helps create a more reliable record of performance when solar reflectance is a relevant requirement or selection criterion.

• Portable measurement method
• Solar reflectance near ambient temperature
• Useful for field and product evaluation
• Supports consistent testing and reporting
• Relevant to reflective surface performance