Work performance in relation to lighting environment in office buildings

摘要： The purpose of this study was to investigate the effect of lighting environment on the work performance. Orthogonal experiments with three-factor and three-level for each factor were designed and carried out in a laboratory aiming to reveal the relationship between lighting illuminance (ILL), uniformity of illuminance (U-ILL), correlated colour temperature (CCT) and workers’ productivity. Twenty-four participants’ work performance was evaluated by subjective questionnaires, objective physiological tests, accompanied with computerized neuro-behavioural tests assessing six kinds of neuro-behavioural functions. Results illustrate that when exposed to high ILL, U-ILL and CCT environment, participants reported highest satisfaction on productivity and attention, while lowest score on stress, difficulty of conducting work and fatigue. The range value and variance analysis from neuro-behavioural tests demonstrated the appropriate level of each factor and the optimal combination. However, they varied with the type of tests illustrating that lighting conditions could influence neuro-behavioural functions differentially. The improvements of perception, learning and memory function of participants were benefited from high ILL, high U-ILL and high/medium CCT. Low ILL, low U-ILL and moderate CCT were appropriate to increase participants’ thinking and executive performance. Moreover, high quality of tear film crystallization was related to higher illuminance. The present study suggests that it is necessary to design personalized illumination environment for particular workplace.