Lighting conditions send crucial environmental cues to help regulate our circadian system and here’s why… | photo courtesy @tangojuliette

Lighting Conditions


My best friend is a lighting genius. Wherever we go, he is certain to make spot-on, insightful observations of the lighting.   He also has a keen ability to capture light in even the simplest of photos taken on his phone. Light was never something I paid much attention to. I knew that I loved to take outdoor breaks throughout the day, but I attributed the invigorating feeling to fresh air and soaking up some Vitamin D from the sun. Then, last year I found myself in a job where I spent a lot of time on the computer. I was in a tiny room with drawn blinds. The only source of light came from the undersurface of cabinets anchored above our work desks. For the first time in my life, I was getting regular headaches.

How does light affect the way our bodies function? How does this, in turn, affect our workplace performance? My investigation into these questions led me to discover the concept of “circadian lighting.” This is defined as “spectrally weighted retinal irradiance that stimulates the human circadian system” (Lighting Research Center, Rensselaer Polytechnic Institute). Our circadian system controls the processes within our body that follow a 24-hour cycle: including regulation of hormones, body temperature, and sleep/wake cycles. A collection of cells called the suprachiasmatic nuclei (SCN) send signals throughout our body to help regulate us to our 24-hour day. Lighting conditions send crucial environmental cues to help regulate our circadian system.  Light travels first to our retina, then to our SCN, and ultimately to the pineal gland, which releases melatonin, the hormone that makes us feel sleepy.

How many hours per day do you spend indoors? Most Americans spend 90% of their time indoors (U.S. Environmental Protection Agency). Exposure to artificial indoor light suppresses melatonin production, thereby disrupting our ability to sleep, regulate body temperature, blood pressure, and glucose levels. Research is connecting disrupted circadian systems to a host of health impairments including cancer, obesity, diabetes, heart disease, depression, mood and sleep disorders, decreased physical and mental performance, decreased productivity and irritability. The number one culprit that disrupts our circadian system is night-time exposure to blue-rich light from screens: namely televisions, phones, and tablets. The blue part of the light spectrum suppresses melatonin to the greatest extent and the LED lights, acclaimed for their energy efficiency, produce more blue light than incandescent or fluorescent lights.

In the workplace, 68% of employees complain about office lighting (American Society of Interior Design). The most common complaints are lights that are too dim and lights that are too harsh.  Both of these can decrease productivity by inducing eyestrain and headaches. What are the lighting conditions in your workplace? How does your body react? Do you ever compromise your posture when seeking better light? A 2012 study published in Behavioral Neuroscience investigated the effects of working typical 8-hour work days in either artificial light or with natural daylight. Simulated laboratory conditions revealed that by the end of the workday, those exposed to natural daylight were significantly more alert and demonstrated significantly greater cognitive performance during work-related tasks.

3 simple strategies to try:
1) Get as much natural lighting as possible! Aim to get at least 60 minutes of outdoor light exposure per day.  When you are inside, try to position yourself near a window.
2) Seek indirect lighting: Direct lighting can strain our eyes and decrease productivity. Indirect lighting distributes light upward towards the ceiling and then reflects it back downward, providing even illumination without eye-strain.
3) If you’re on the computer late at night, consider downloading software that regulates your computer’s color display to sync with our 24 hour days. F.lux is free and can be downloaded at https://justgetflux.com/

GIG DESIGN | Occupational Performance

STRATEGY^context

DESIGN^interceptive | Consider your behavioral standards towards lighting through exploration of your behavior to lighting.

STRATEGY^occupation

DESIGN^body position | Consider the patterns required of your body as you interact with the effects of lighting during work tasks.

STRATEGY^sense

DESIGN^under responsive | Consider your body capacity needs with lighting to attend to your task.


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