Demonstration of Outdoor Lighting for Maximizing Perceptions of Safety and Security

Working with project partners from the Seattle Lighting Design Laboratory, the Lighting Research Center (LRC) will identify a suitable outdoor lighting installation in a parking lot and conduct evaluations of energy and power use, visual responses of people in and approaching the outdoor location, and subjective ratings of safety and personal security while viewing and occupying the location. The design of the lighting installation will utilize published research on the spectral sensitivity of the human visual system for scene brightness perception and on the relationships between scene brightness and perception of safety and security previously published by the LRC project team. The proposed project will consist of a full-scale outdoor lighting demonstration at a parking lot facility within BPA service territory. The demonstration will be based on a proposed specification method for maximizing perceptions of safety and security of occupants, taking advantage of the differential spectral (color) sensitivity of the human visual system for brightness perception at nighttime light levels. Sensations of brightness are in turn strongly related to perceptions of personal safety and security in outdoor locations. It is anticipated that using white light sources such as a lighting emitting diode (LED) illumination in place of conventional high pressure sodium (HPS) illumination energy savings of 40-50% will be possible while maintaining perceptions of brightness, safety, and security.