Ambiguities regarding the relationship between office lighting and subjective alertness: An exploratory field study in a Dutch office landscape

• Published in: Building and environment 2018-09, Vol.142, p.130-138
• Main Authors: van Duijnhoven, J., Aarts, M.P.J., Rosemann, A.L.P., Kort, H.S.M.
• Format: Article
• Language: English
• Subjects: Alertness; Circadian rhythm; Data analysis; Health; Human exposure; Illuminance; Indoor environment; Karolinska sleepiness scale; Light effects; Lighting; Mathematical analysis; Occupational health; Office; Office lighting; Statistical analysis
• ISSN: 0360-1323; 1873-684X
• DOI: 10.1016/j.buildenv.2018.06.011

The current field study investigated the ambiguities regarding the relationship between office lighting and subjective alertness. In laboratory studies, light-induced effects were demonstrated. Field studies are essential to prove the validity of these results and the potential recommendations for lighting in future buildings. Therefore, lighting measurements and subjective health data were gathered in a Dutch office environment. Health data was collected by questionnaires and includes data on functional health, wellbeing and alertness. Multiple general, environmental, and personal variables were identified as confounders for the relationship between light and alertness. For six out of the total 46 participants a statistically significant correlation was found between horizontal illuminance (Ehor) and subjective alertness. Further research needs to incorporate a larger sample size and more potential confounders for the relationship between Ehor and alertness. Further research including these recommendations may explain why certain people respond to light while others do not. •Link between horizontal illuminance (Ehor) and subjective alertness (SA) investigated.•General, environmental and personal confounders for relationship between Ehor and SA.•Link between Ehor and SA established for a certain percentage of the sample size.•Further research should focus on possibilities to explain this percentage.•This study highlights the importance of validating laboratory study results in field studies.