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In modern workplaces, the well-being and productivity of employees are increasingly recognized as essential for organizational success. This study explores the impact of lighting interventions—specifically, Correlated Color Temperature (CCT) and illumination intensity—on stress and cognitive function restoration among office workers. A between-subjects experimental design involving 100 participants assessed the effects of various lighting conditions on stress responses and cognitive performance after exposure to stress-inducing and cognitive fatigue tasks. Five experimental conditions were studied: 100 lux & 7000 K, 100 lux & 3000 K, 1000 lux & 7000 K, 1000 lux & 3000 K, and a baseline condition of 500 lux at 3700 K. Results indicated that lighting conditions significantly influence both physiological stress markers (such as skin conductance level and heart rate) and cognitive performance. Specifically, warm, and dimmed lighting (3000 K, 100 lux) effectively reduced stress markers and perceived stress levels, aligning with theories suggesting the calming effects of warmer white light tones. Conversely, cooler lighting (7000 K) was associated with enhanced cognitive performance and reduced cognitive fatigue, potentially due to its similarity to natural daylight, stimulating an alert state conducive to mental tasks. These findings suggest that lighting interventions offer a non-intrusive strategy to improve well-being and productivity in office environments, particularly addressing acute symptoms.
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Subjective Impression of an Office with Biophilic Design and Blue Lighting: A Pilot Study
This paper investigates and compares people’s subjective impression of an office with a biophilic design and blue lighting. Existing studies have examined their influence on perception separately, but how they compare is unclear. Additionally, only a few studies have used an office setting as a case study. To address this research gap, this study collected people’s ratings and rankings of four simulated interior scenes of a private office using an online survey. The scenes include blue lighting, a biophilic design with daylight and view, a biophilic design with indoor plants, and a non-biophilic baseline with conventional white lighting. A total of 284 complete responses were collected and analyzed using a mixed-effect model. It was found that the two biophilic designs improved people’s perception of the office compared to the base case. The biophilic design with access to daylight and view outperformed the space with indoor plants in all the examined perceptual categories, specifically how the office space was perceived by participants as brighter, more comfortable, and spacious. On the contrary, the space with blue lighting decreased people’s ratings in most perceptual attributes in comparison to the baseline. The negative influence was notably significant in how lively, comfortable, bright, and appealing the space was perceived as being by participants. Subjects’ preference rankings of the four simulated office spaces showed a similar pattern.
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- Award ID(s):
- 1640818
- PAR ID:
- 10393472
- Date Published:
- Journal Name:
- Buildings
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2075-5309
- Page Range / eLocation ID:
- 42
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3390/buildings13010042
