Interactions Between Light and Environments – Impact on Non-visual Effects Evaluation

Knowing the characteristics of light reaching the occupants’ eyes is fundamental to evaluate the human nonvisual responses. These characteristics depend on the interactions between light and the built environment. To deeply analyze this effect, the spectral irradiance at the eye level were measured and the related circadian responses were calculated in a test room where 21 different light scenes are set, combining 7 different wall colors and 3 CCTs. Variations of circadian stimulus (CS) for colored walls in comparison to neutral configurations were found. Furthermore, lighting simulations were performed. Spectral irradiance was obtained by means of both basic and accurate computational approaches. The outputs were compared to measurements. It was found that, despite more accurate lighting simulations perform better than the basic ones, results are not always completely reliable.