Illuminating the Workplace: How Lighting Impacts our Health at Work

Lighting is such a part of our daily lives that we hardly stop to acknowledge it unless it interferes with our ability to perform activities, like trying to read a menu in a dimly lit restaurant or forgetting your sunglasses at the beach. Lighting, defined as “the application of the optical radiation in a built environment, (Dilaura, 2012)” contributes to our daily function whether its assistive or hindering. The workplace is a built environment where many people spend the majority of waking hours, yet most of us are not lucky enough to have the corner suite office with a view. Beyond the windowless workplace, special consideration is warranted for employees with low vision or those who perform shift work.

In the workplace, there are many basic considerations for lighting including the type of lighting (ambient, task, accent), the bulb type (LED, halogen, fluorescent), the cost versus energy savings, and the visual experience of the setting. It’s important to note that “bad” lighting does not equal lack of lighting, but “bad” lighting can be too bright or the wrong spectrum. One dimension of lighting is brightness, which is measured in Lux, or footcandles. Recommendations for brightness in various settings have been established and depend on the task at hand, for example in a doctor’s office, the exam room and the waiting area have different light requirements that depend on activities performed in the space.

Lighting is often examined in the ergonomic assessment process, as poor lighting can create eye strain and suboptimal posture. The impact of poor lighting at work, however, can impact our well-being in a number of other ways that extend beyond basic ergonomics. The properties of light (including amount of exposure, spectrum, timing of exposure, and duration) affect various brain pathways—having physiological and behavioral outcomes that impact our performance, well being, and personal comfort at work, as described here.

Bad lighting negatively affects mood at work.

Research indicates that sufferers of Seasonal Affective Disorder (SAD) have inadequate light exposure, which can be exacerbated by time spent in indoor workspaces. Mood regulation depends on illumination in the 24-hour period, which is another reason why natural lighting is so important for people who suffer from SAD. In other words, the presence of variable light during the day impacts our mood and nervous system in different ways than continuous, non-changing indoor lighting. Furthermore, research has revealed gender differences related to color temperature (warm versus cool hues) and negative effect on mood in office settings (Knez & Enmarker, 1998).

Bad lighting affects our circadian rhythm, sleep, and alertness levels.

Exposure to light trains our biological clock, and the recent discovery of new photoreceptors in our eyes have pointed researchers to studying the importance of vertical illuminance (Berson 2002). In other words, your body’s orientation to time of day related to the angle of natural light is important, and without this exposure the body might become sleepy at inopportune times or may keep you from falling asleep at night time. (We’ve all heard the sleep hygiene recommendation of no screens before bedtime -- it suppresses melatonin production (Lewy et al 1980).)

“Healthy” lighting increases work performance.

Daytime bright light increases alertness which has a positive impact on motivation, morale, and productivity. Insufficient light levels cause lowered concentration and tiredness, which increases errors at work. Additionally, sufficient lighting, the reduction of glare, and adequate visual contrast improve cognitive and motor functions related to task performance. The effects are obvious in some cases, for example, think about the lighting demands for precision work of surgeon or a jeweler, and how important adequate lighting is to their job performance.

Forward thinking workplaces consider the therapeutic combination of daylight and electric lighting how it relates to the health of their employees. Importantly, exposure to variable light is key to keeping our circadian rhythms tuned. If natural light is lacking, taking outdoor breaks through walking meetings or lunches is a strategy to keeping our internal clocks healthy. Alternatively, one innovative solution to the lack of daylight in the office is the concept of artificial “circadian lighting,” which is technologically advanced LED that mimics natural lighting by changing over the course of the day.

Looking for the light at work? Contact The Rising Workplace to learn more about lighting assessment and workplace ergonomics at nikkiw@risingworkplace.com.

Dr, Nikki Weiner OTD, OTR/L, AOEAS

References:

Aries, M. B. C. (2005). Human lighting demands: healthy lighting in an office environment (pp. 0212-0212). Technische Universiteit Eindhoven, Faculteit Bouwkunde.

Berson, D. M., Dunn, F. A., & Takao, M. (2002). Phototransduction by retinal ganglion cells that set the circadian clock. Science, 295(5557), 1070-1073.

DiLaura, D.K. Houser, R., Mistrick et al. (2012). IES Lighting Handbook: Reference and Application, 10th ed. New York: Illuminating Engineering Society of North America.

Figueiro, M.G. & Rea, M. S. (2017) Vision and Lighting. Ergonomic Workplace Design for Health, Wellness, and Productivity. Ed. Hedge, A. CRC Press.

Knez, I., & Enmarker, I. (1998). Effects of Office Lighting on Mood and Cognitive Performance And A Gender Effect in Work-xRelated Judgment. Environment and Behavior, 30(4), 553–567. https://doi.org/10.1177/001391659803000408

Lewy, A. J., Wehr, T. A., Goodwin, F. K., Newsome, D. A., & Markey, S. P. (1980). Light suppresses melatonin secretion in humans. Science, 210(4475), 1267-1269.