Glass in building; determination of light transmittance, solar direct transmittance, total solar energy transmittance and ultraviolet transmittance, and related glazing factors

This document establishes a comprehensive methodology for evaluating the optical characteristics of architectural glass. It defines precise procedures for measuring light transmittance, solar energy transmittance, and the total solar energy factor, which includes direct sunlight transmission. Additionally, the standard addresses the determination of ultraviolet transmittance and various gloss coefficients associated with the glazing material. These parameters are critical for understanding how glass interacts with solar radiation and visible light in building applications. The testing protocols outlined within ensure consistent and reproducible results across different laboratories and manufacturing facilities. By providing a unified framework, this reference enables accurate assessment of thermal and visual properties essential for energy efficiency calculations and architectural design. It covers the necessary experimental conditions, instrumentation requirements, and calculation methods to derive reliable data regarding the interaction of light and glass. This approach supports the industry in maintaining quality and performance standards for fenestration products used in construction environments worldwide.