Standards Development

Scope

This document applies to the broad range of materials and systems, e.g. fabric shades, venetian blinds, prismatic glass, etc., that are used on windows and skylights to control daylight, sunlight, glare, privacy, and view to the outdoors. It specifies procedures for producing comprehensive angle-dependent, solar-optical scattering data that can then be used to compute a wide range of performance metrics.

This document specifies procedures for:

a)       characterizing angle-dependent, optical properties (transmittance, reflectance, absorptance) of glazing and shading materials and systems, i.e. "complex fenestration systems" (CFS) and then

b)       generating tabulated bidirectional scattering distribution function (BSDF) data sets for use as input to simulation tools or standardized calculation methods such as the comprehensive hourly calculation method defined in ISO/CIE 10916.

This document establishes generally applicable methods for BSDF characterization of CFS for evaluation of performance criteria based on spatially resolved (luminance, solar patch) and/or integral radiation quantities (illuminance, solar irradiance) and thus on definitions and specifications for generating tabulated BSDF data. The methods apply for the full solar spectral range from 280 nm to 4000 nm including ultraviolet, visible and infrared regions.

The subsequent derivation of analytical models in order to characterize some types of CFS with a large number of similar variations is not included in this document.

Characterization of CFS as a function of wavelength (spectrally resolved) or position on a non-homogeneous surface is also not included in the scope of this document.