What is Circadian Lighting Design?
There is increasing pressure to design buildings that support occupant’s wellbeing and circadian health; one of the ways this can be achieved is through circadian lighting. Find out about the fundamentals of circadian lighting here.
As mentioned in previous articles, since the discovery of photosensitive retinal ganglion cells (ipRGCs) in the retina and an understanding how of these cells work has led to a much better comprehension of how our circadian rhythms work. Our eyes receive signals from light which determines whether we feel awake or sleepy. If retinal ganglion cells do not receive light for two hours, melatonin is produced, triggering the sleep or circadian cycle.
With many of us spending up to 90% of the day indoors, and often much of that time staring at a computer screen, TV, or smartphone, we lose our connection with natural light, and our sleep-wake cycle can get out of sync. We’ve gone into more detail on the science behind circadian rhythms here.
Circadian lighting design considers lighting direction, timing, intensity, colour, wavelength and the aesthetic of light - creating a solution that both looks amazing and is suitable for the various tasks carried out within a building. Designers and architects need to understand how all of the elements within an environment can impact occupant health and wellbeing, and importantly their circadian cycles. As light is the most powerful synchronizer of the human circadian clock, it is an essential element to perfect.
Our algorithm mimics the colour and intensity of natural light over a 24 hour period; it automatically changes throughout the day, beginning with a warm amber light at sunrise, slowly changing into a cooler, brighter light during the day, before warming back into an amber light at sunset. In this way, specific colours of the visible light spectrum are designed to precisely provide circadian stimuli to building occupants in the morning and ensure that the lighting does not interfere with their natural body clock later, ensuring they get a better night’s sleep. Melanopic light intensity varies for different workplace areas, e.g. break rooms, meeting rooms, etc. Everything is completely customizable, allowing all needs to be accommodated, e.g. if a resident in a care home has an eyesight condition and requires a higher level of illumination, the lighting in their room can be adjusted without it impacting anything else in the home.
WELL is one of the most established standards for measuring features within the built environment that impact human health and wellbeing. It covers a range of areas, including air, water, nourishment, light, fitness, comfort, and mind, to improve nutrition, fitness, mood, sleep, comfort, and performance.
The ‘light’ segment of the standard aims to minimise disruption to human circadian cycles; it sets out guidance that helps designers and architects to support a good sleep pattern, improve productivity and provide a higher quality of illumination for the various tasks completed in different built environments. Find out more about other ways of measuring the effectiveness of circadian lighting.
An example of colour variation in Heanor Park care home.
Beginning with a ‘smart’ circadian lighting system opens up opportunities for further benefits within the built environment, offering designers more flexibility.
The circadian lighting system can speak to nurse call systems, fire alarm systems and it can react to external cues by integrating with sensors. A cloud light scene can be used to emulate the feeling of clouds passing overhead; daylight saving mode can reduce the intensity of the artificial lighting when natural light shining into a room is at a high enough level, and voice activation can give residence more control over their own environment.
In an office environment, you may want the full benefits of healthy/circadian lighting and the ability to walk into a meeting room and have it respond to a command, e.g. ‘presentation mode’ whereby the lights dim, the blinds shut, and the TV screen comes on.
In a school, circadian lighting can be a valuable asset in maintaining concentration and productivity levels, but you may also want the ability to have an ‘exam mode’ or ‘creativity mode’ which aims to enhance the building occupant’s experience and allow them to perform better in their task.
Circadian lighting design can open up further possibilities that bring added comfort and enjoyment to building occupants of all kinds, creating an immersive experience that aims to make occupant lives easier and healthier.