Van de Perre, Smet, Hanselaer, Dujardin, and Ryckaert evaluated the consequences of different lightscapes in windowless offices. They report that “A two-interval-forced-choice experiment was conducted with the 20 lighting scenes derived from five CCTs [correlated color temperatures] (2500–10 000 K) and four luminances (12–120 cd/m²). The results from 20 observers showed that a higher wall luminance significantly increased brightness.
Trop and colleagues evaluated lighting conditions in which people felt safe in public spaces. They learned via a literature review that “while higher intensity is usually associated with better safety perception, some studies . . . point out the diminishing returns or plateau-escarpment of illumination levels above 10lx. Second, mismatch between perception of safety and perception of other qualities of PSL is also apparent . . . indicating that place intended functionality should be considered (e.g., parking lot comfort associated with higher CCT. . .
Light, whether daylight, moonlight, or produced via some sort of technology, has a significant effect on our mental and physical wellbeing, how we think and behave. Neuroscience research indicates how to best tune the type of light we experience and, when artificially generated, that light’s color and intensity and distribution, to encourage desired design-based outcomes.
Figueiro and Pedler review important issues related to circadian lighting. They make wellbeing-enhancing suggestions: “Open the window shades in your home or office but be careful to avoid creating glare. . . . When sitting by a window, try to face it. . . . If you cannot work facing a window, add extra table or floor lamps next to your work area. A do-it-yourself (DIY) circadian lighting device is another option. If you have access to windows, make sure the shades are open and that you are facing the window. . . .
Recently completed research indicates that experiencing higher levels of light at night may not be healthy for pregnant people. Investigators report in a study published in the American Journal of Obstetrics and Gynecology Maternal Fetal Medicine that “Pregnant adults who had greater light exposure three hours prior to sleep had a higher risk of developing gestational diabetes than those who had less exposure during this period. . . . Gestational diabetes is a type of diabetes that occurs during pregnancy. It can cause harm to both mother and baby.
Effort-linked recommendations
Geng and colleagues studied the effects of light color on employee decisions. They found “that blue light more likely promotes individuals choosing the farsighted intertemporal option (i.e., delayed but larger payment) than red light. . . . The current study demonstrates the effectiveness of light color and provides a solution to nudge people to make farsighted choices.”
A study published in the journal of the European Association for the Study of Diabetes (Diabetologia) will support better management of outdoor artificial light at night (LAN) and actions such as using black-out curtains in bedrooms. Yu and colleagues determined that LAN “is associated with impaired blood glucose control and an increased risk of diabetes. . . .
Grant and colleagues investigated falls in care homes by elderly (mean age 81 +/- 12 years old) residents. They report that some test locations “had solid-state lighting installed throughout the facility that changed in intensity and spectrum to increase short-wavelength (blue light) exposure during the day (6 am–6 pm) and decrease it overnight (6 pm–6 am). The control sites retained standard lighting with no change in intensity or spectrum throughout the day. The number of falls aggregated from medical records were assessed over an approximately 24-month interval. . .
Circadian lighting for better lives