Abstract
A model-scale study of glare has been made in order to investigate the tolerable levels of luminance of a luminous ceiling. The model represented an unfurnished room with a diffusing luminous ceiling; the reflection factors of the walls and floor could be altered to give a series of room surfaces from all white to all black. The observers viewed the model from one end, and made their glare assessments by adjusting the ceiling luminance to specified glare levels while looking towards the opposite wall.
The results indicate that, under the experimental conditions, the ceiling luminance for the level of glare equal to the mean of the criteria ‘just acceptable’ and ‘just uncomfortable’ is of the order of 150 ft-L with room surfaces of normal reflectances. The modifying effect of room surface reflectances is complex, because light surfaces receiving high illumination themselves act as secondary sources of glare.
Get full access to this article
View all access options for this article.