A simple method for the appraisal of glare in street lighting

Abstract

A graphical method for the quantitative assessment of discomfort and disability glare in street lighting is described. The method is based on two groups of experiments which were carried out independently of each other. The results, which show good agreement, reveal the relationship between discomfort sensations and the relevant photometric and geometric parameters. By applying results of earlier studies the system can be extended to cover different geometries of the installation and different colours of light source. Disability glare is included by transforming the equation representing the experimental findings of discomfort so that one side becomes identical with the expression for the equivalent veiling luminance. Graphical presentation enables the discomfort glare to be assessed in terms of the Glare Marks associated with different sensations of discomfort glare. A network facilitates computation of the equivalent veiling luminance.