How Does Lighting Affect Wayfinding after Dark?

Saleheh Bokharaei (Shahid Beheshti University)
Jack L. Nasar (The Ohio State University)

People feel safer if the environment helps them orient and find their way around. Micro and macro-scale characteristics of streets can affect orientation and wayfinding (Lynch, Appleyard, & Meyer, 1965). Horizontal and vertical differentiation (paths and landmarks), and simpler layout can help people find their way around (Nasar & Cubukcu, 2005). Most research focuses on wayfinding during the day (Hill, 2013), but researchers have called for studies after dark (Fotios, Unwin, & Farrall, 2015; Bovy & Stern, 2012, Kumagai & Tack, 2005; Kettunen, et al, 2015; Winter, Raubal, & Nothegger, 2005). Our study focused on the effects of the lighting of sidewalks/streets on wayfinding after dark. We created a video simulation of a route (after dark) –with the lighting consistent throughout the route (overhead, uniform, fairly bright) – from a subway station to an intersection turning to another route. We also created eight photos at choice point along the route in which we manipulated lighting of the route for horizontal differentiation (lighting along the path, landscape highlighting, fixture spacing and cadence) and vertical differentiation (facade illumination, lighting at the end). We kept all other features constant. The study used pair-wise photo choices. We had 30 participants view paired photos in randomized order. The instructions told them that they were trying to find the destination and asked them to choose the photo for the route they'd most likely take. The results confirmed effects of differentiation on wayfinding, and suggest ways lighting designers can improve wayfinding.

Keywords: environmental appraisal; safety; reassurance; lighting; wayfinding