Perceived adequacy of illumination and pedestrians’ night-time experiences in urban obscured spaces: A case of London

Abstract

This paper discusses lighting for pedestrian in urban obscured spaces and how perceived adequacy of illumination (PAI) might enhance pedestrians’ night-time experiences. A conventional approach is to evaluate human responses under road lighting of different illuminance, but this alone does not enable an optimum light level to be identified. In this study, a total of 30 participants (19 females and 11 males) visited 10 different urban obscured spaces underneath bridges in London. Their night-time experiences such as feelings, suitability of a space, discomfort glare and facial recognition were compared with horizontal illuminance levels and percentages of PAI. The result indicates that horizontal illuminance was associated with perceived quality of facial recognition, perceived ratings of pleasantness and liveliness. However, higher lighting does not seem to result in higher qualities of other night-time experiences in uncontrolled environments. Spaces with higher percentage of PAI are more strongly associated with an increase in pedestrians’ perceptions of pleasantness, liveliness, suitability of spaces and ratings of facial recognition. Perceived level of discomfort glare was found not to be related with neither illuminance level nor PAI percentages. The paper suggests that PAI can be a moderate indicator of an overall night-time experience for pedestrians in obscured spaces.