Why the right lighting is a must-have for healthy workplaces

Researchers are now telling us how light can play a big role in employee health, happiness and productivity

10 janvier 2019

As circadian science moves from the fringes to the mainstream – owing in part to the growing US$4.2 trillion wellness industry – new lighting systems aimed at improving health and productivity are headed for the workplace.

“Companies are starting to think about their real estate as a means for improving the health of their employees,” says Keara Fanning, who leads a sustainability practice at JLL. “As humans, we evolved to wake up with the sun and go to sleep at sundown. When our lighting does the opposite of that, it affects us.”

Light at the end of the meeting room

People have long associated cloudy days with fatigue and gloominess. But only recently did scientists prove the correlation.

In the early 2000s, researchers identified photoreceptors in the eye which instead of helping us see, help set the circadian clock in our body. A different set of researchers also found that these receptors were most sensitive to blue wavelengths of light and that these wavelengths suppress the production of melatonin, the hormone that makes the body ready for sleep. This means that intense exposure to blue light can keep you awake at night – and help you focus during the day.

The research has influenced “circadian hacks” – from blue-light-blocking glasses for nighttime, to sun lamps that can help with everything from alertness to seasonal depression.

The basic principles are being applied to workplaces to improve employee health.

At the architecture firm Arup Group’s Boston office, for example, a circadian lighting design that changes color temperature and intensity throughout the day was installed to help meet one of the features of the WELL Building Standard, a program for buildings, interior spaces and communities seeking to implement, validate and measure features that support and advance human health and wellness. The office balances available natural lighting and an indirect electric lighting design that creates a balanced and well-lit space. Warmer colored lights, which naturally reduce the amount of insomnia-inducing blue, are used as evening approaches.

At Delos’ WELL Certified Platinum headquarters in New York City’s Meatpacking District, a lighting system combines dynamic, color-changing LEDs with daylight and occupancy sensors to achieve desired light levels and quality throughout the day. This circadian lighting system aims to keep the body’s internal clock ticking on the 24-hour cycle by emitting bright bluish light during the day, suppressing melatonin, and dim yellowish light as the evening approaches, allowing melatonin to flow.

Because people spend much of their life at work, office lighting can have an even bigger impact on the body’s signals that it is day or nighttime.

“The body likes a clear message,” says Shruti Koparkar, who leads corporate strategy and development at Ecosense Lighting, a company that is developing a proprietary lighting technology with a particular focus on biologically effective lighting through spectral modulation. “A lot of light with significant blue content signals day and less light with diminished blue content signals night – the greater the differential, the easier it is for our bodies to adapt to a 24 hour day-night cycle. If there is not much difference, the body is confused.”

Natural light and design

Natural daylight is ideal in an office environment because it is the fullest spectrum of light that includes all colors, and it provides the clearest visibility.

An open office plan that allows for the light to stream through the workplace without being blocked by any walls has helped many companies achieve this, Fanning says.

“Ideally, you want every worker to have access to the view,” Fanning says. “But where that’s not possible, you can punch through the roof to put a lightwell into a building, or bounce light off of mirrors to bring it into a space.”

Jessica Cooper, Chief Commercial Officer at the International WELL Building Institute, which delivers the WELL Building Standard, says that “glare management” is an important consideration when designing for employee health and comfort, but that the amount of time in which the sun is causing direct glare in a given area is typically small.

“With manual blinds, employees often close the shades for the ten minutes of glare but forget to open them again,” she says. “That works against the goal of having access to daylight and views as often as possible throughout the space.”

Turning to automation

Enter automated shading systems. Mirvac’s WELL Certified Gold headquarters in Sydney takes an innovative approach. Their building is enclosed with triple layers of glass which are separated by small cavities. Within one of these cavities, between two layers of glass, sits a timber blind system that automatically adjusts as the sun moves around the building over the course of the day.

The façade supports energy efficiency and optimal thermal insulation, while also reducing glare to support visual comfort. When the wood louvers are completely closed, they emit a soft golden hue of light that brightens the interior space. When glare is not an issue, the blinds are fully open, providing stunning views to the outside.

“Automated shading is becoming more common, but is still fairly unique and requires an additional investment,” Cooper says. “The solution requires that the shades be motorized and programmed to raise and lower depending on the positioning of the sun. Some technologies will respond to daylight sensors on the outside and inside of building, making the shades even more responsive to light levels and glare.”

In spaces where daylight is not available, a lighting system that most closely mimics it is the next best thing. Ecosense ran an informal experiment on its own employees using a prototype of their dynamic lighting technology in a room with no windows. For the first week, participants sat under static lights.

During the second week, employees sat in front of light panels that changed in color temperature from cool to warm as the day passed. As evening fell, employees staying late experienced even warmer light.

Participants found the transitions helped – one called the afternoon light “calming” and good for adjusting to the low light during the commute home.

“Everything in nature is either moving or changing,” Koparkar says. “This experiment revealed to us that perhaps humans are happier when the lighting most closely reflects this. The ideal solution is to get outside, but when we can’t do that, maybe we can bring the outside in.”