Effect of thermal conditions and light source type on visual comfort appraisal

Abstract

The objective of the experiment described was to test the hypothesis that thermal conditions and light source type have an effect on visual comfort appraisal. Twenty subjects evaluated the visual and thermal comfort at two temperature conditions (20.5°C and 27°C) and under three light source (daylight, decode light and combined lighting), at a constant 300 lx illuminance. The hypothesis that thermal conditions influence visual comfort appraisal was not verified. However, it was found that light source type has an important influence on visual preference: the subjects preferred a lower illuminance under electric light than under daylight. A sex difference with regard to visual comfort was also found. In addition, sky conditions influence visual perception and it was found that correlated colour temperature had a tendency to affect visual and thermal perception.