Search results for "Circadian effect"
showing 3 items of 3 documents
Daylighting offices: A first step toward an analysis of photobiological effects for design practice purposes
2014
Abstract The research presented in this paper reports an analysis of daylight in three offices with different exposures and characteristics located in Naples (Italy). The goal was to fully investigate daylight characteristics, also considering the circadian impact of daylight entering these offices, with the hope to develop guidelines to better assess daylight quality in built environments. One of the main findings of this research is that the spectral distributions and CCTs of the light reaching the eye of a person seated at the desk in these offices are similar irrespective of the offices' different characteristics (dimensions, surfaces' spectral reflectances, external obstructions, etc.)…
Lighting in educational environments: An example of a complete analysis of the effects of daylight and electric light on occupants
2013
Abstract Light induces not only visual responses but also non-visual effects, indeed it affects performance, mood, attention and influences the synchronization of the biological clock. Duration, timing, intensity and the spectral power distribution of the light that reaches the eyes can have influence on human circadian rhythm and consequently on health. Given the important impact of the non-visual responses on people wellbeing, developing a model that allows lighting designers to predict them is a fundamental goal. In this paper a case study is reported: a series of measurements were carried out in a University classroom in order to study daylight and electric light characteristics and als…
Indoor artificial lighting: Prediction of the circadian effects of different spectral power distributions.
2014
The study presented in this paper aims to evaluate if and how the environment affects the circadian impact of a light source by predicting circadian stimulus (CS) resulting from the exposure to different light scenes, using equations reported in studies by Rea et al. The main findings are: (1) Above 600 lx at eye level the increase of CS is little; (2) Between 50 lx and 200 lx at the eye level an increase of only 50 lx determines a significant increase of CS; (3) Light sources with correlated colour temperatures between 2900 K and 4200 K have similar impacts on the circadian system according to the calculation method used; (4) Even an almost neutral environment affects the circadian impact…