Effects of four workplace lighting technologies on perception, cognition and affective state (English)

Light-emitting diodes (LED) are becoming an increasingly common lighting option for industrial applications, offering superior power efficiency and longevity relative to conventional fluorescent technologies. This study examined the visual perceptual, affective and cognitive implications of equipping temporary military shelters with either fluorescent or one of three advanced LED lighting systems with varied color temperature and luminance. Twenty-four volunteers were each tested over the course of five consecutive days, including a practice session and four test sessions, one for each of the lighting conditions. Volunteers showed highest visual acuity as measured on symbol identification and color recognition tasks with LED relative to fluorescent lighting and this effect was greatest at highest color temperatures. In terms of psychological and cognitive performance, volunteers showed increased fatigue ratings with fluorescent relative to LED, and this effect was associated with slower response times on tasks measuring spatial and verbal memory. Recent increases in the number of LED technologies being incorporated into industrial lighting applications carry implications for worker performance. We provide evidence that these advanced lighting technologies can promote increased alertness and visual cognitive efficiency among workers when compared to more traditional alternatives.