Washington, November 2 : A study conducted by British researchers suggests that office workers can be helped in staying more alert and less sleepy during the day by changing traditional white-light lighting to blue-enriched white light.
Researchers from the Surrey Sleep Centre at the University of Surrey, who partnered with Philips Lighting for the study, said that this approach can lead to significant improvements in subjective measures of positive moods, work performance, fatigue in the evening, irritability, ability to concentrate and focus and eye strain.
The workers exposed to blue-enriched white light during the study also reported improved sleep at night, the researchers say.
Professor Derk-Jan Dijk, who lead the experiment, believes that the blue-enriched white light is more effective because it targets a recently discovered novel photoreceptor in the eye.
The researcher revealed that the study involved 104 white-collar workers on two office floors.
After baseline assessments under existing lighting conditions, every participant was exposed to two new lighting conditions, each lasting four weeks. While one consisted of blue-enriched white light, the other consisted of white light.
The order was balanced between the floors.
The researchers used questionnaire and rating scales to assess alertness, mood, sleep quality, performance, mental effort, headache and eye strain, and mood throughout the eight-week intervention.
"This research may indeed imply that our currently used artificial office lighting is suboptimal for maintaining alertness," the Science Daily quoted Prof. Dijk as saying.
The research has been published in the Scandinavian Journal of Work, Environment and Health.