Hidden Treads: The Issue of Nonuniform Lighting on Stairs

Lighting design is an important element for human factors practitioners to assess during hazard analyses of staircases. Insufficient visual information or environmental features can affect an individual’s ability to successfully navigate a staircase. Specifically, the ability to delineate between a nosing and the step below is critical for individuals to appropriately place their foot. Poor lighting system designs or improperly maintained lighting can increase the likelihood of falls. This work describes a case study involving a fall from a misstep on a staircase with LED lighting strips under only half of the nosings in an alternating pattern. This type of lighting design demonstrates that light patterns can disrupt the perception of the delineated nosings in the same manner as patterned flooring material. This analysis provides guidance for designers and practitioners when determining the adequacy of lighting on staircases, including the uniformity of lighting necessary for perception of transitions along stairways.