Article Review: Why Light Matters: Designing with Circadian Health in Mind – Metropolis

“Architecture is the masterly, correct and magnificent play of volumes brought together in light.” - Le Corbusier. It has been centuries of this pattern, wake up, drive, work, drive home in the dark. The shifts in color during the day regulate human physiology. Views and daylight have been scientifically illustrated to both reduce the length of time to heal as well as the need for pain medication, according to studies by Dr. Roger Ulrich, Visiting Professor at both Aalborg University in Denmark and the Center for Healthcare Building Research at Chalmers University of Technology, Sweden. If humans’ body rhythms are healthy and routine, circulation and blood flow peak at nearly the same time daily, and digestive and kidney function have their optimal timing as well.

6 principles for designing spaces that support circadian health: (1) provide blue light and warm light at strategic times, (2) body clock ≠ day night cycle, (3) know the inhabitant, (4) maximize daylight exposure, (5) supplement with electric lights, and (6) materials matter.

“Provide blue light and warm light at strategic times. The eye provides both vision and temporal regulation. The visual system have a peak sensitivity to green light. Ganglion cells have a peak sensitivity to blueish light. Blueish light produces two effects: It provides an alerting effect similar to coffee, and it regulates our body clock. At 24.3 hours, the human clock is slightly longer than the 24 hour daily cycle. The proper light stimulus received in morning hours will reduce the 24.3 hour cycle while light exposure in the evening can advance the cycle. The former allows you to fall asleep earlier while the latter can postpone your bedtime, reducing sleep time, resulting in fatigue or a lack of alertness the following day, and potentially making you less productive. If the pattern continues, it can generate long term health consequences. When will occupants be in the spaces that are being designed? Are they working a 9-5 schedule, a swing shift or night shift? Where will they be at the times that are the crucial for light exposure? Each of these aspects should be considered and could point toward solutions that might not be intuitive. For instance, in a current hospital project, studies on how the space would be used showed that patients would be up early and in social spaces in the morning hours. This dictated that the circadian supportive light solution should be focused in the common spaces rather than the patient rooms to maximize light exposure at the most beneficial time of the day. Ensure that daylight solution is routinely available. A daylight solution that needs to be mediated by blinds or roller shades due to glare or thermal discomfort can essentially eliminate the circadian resource as well as the accompanying view. Not all light is created equal, but thankfully we can understand the spectral content of the light resource and choose solutions that meet the qualities desired by a circadian supportive resource. By comparing spectral power distributions (how much of specific colors are included within a light source) one can deploy lighting solutions that are tailored to specific circumstances. Tunable fixtures, or those that can change color, subtly and gradually change the light source throughout the day and can add variable aesthetics to the physiological and functional aspects of lighting solutions.” -http://www.metropolismag.com/interiors/healthcare-interiors/why-light-matters-designing-with-circadian-health-in-mind/

Basically if we can educate people on what circadian rhythm is and how we are hurting our bodies, we can start designing more places with better lighting. And we can change the health of people by different lighting and more daylight.