Color Coded

How color-temperature tuning affects shoppers’ – and sales associates’ – behavior
Posted April 20, 2015

What could humans possibly have in common with cyanobacteria, fungi and other animal species?

The answer: We share circadian rhythms – the mental, physical and behavioral changes that usually follow a 24-hour cycle and partly drive our sleep patterns, wakefulness and bodily functions like temperature and blood pressure. These patterns and functions are largely affected by cycles of light and darkness; color has an effect, as well.

That’s why avoiding certain colors of light at night – like the blue illumination produced by your smartphone or computer – isn’t just an old wives’ tale. The hue actually suppresses the body’s production of melatonin (the hormone that cues tiredness) and can disrupt your sleep cycle. 

The healthcare industry has been privy to this phenomenon for a while, utilizing the information to design lighting that can enhance nurses’ nightshifts, when a mistake caused by an out-of-whack sleep schedule could mean the difference between life and death.

While shopping isn’t normally a life-or-death situation, it’s important to keep customers’ (and sales associates’) health in mind. Retailers with static lighting should stop to think: What effect does this have on my shoppers and employees?  

Designers know the importance of representing a retailer’s product as accurately as possible; you want to avoid a situation where an item’s in-store appearance differs from its actual features. That means lighting aimed at product should be white, not colored.

Setting aside product-illumination practices, what effect does colored ambient lighting have?  

Levia Lew, principal at Reveal Design Group (New York), explains that it does affect perceptions: “Restaurants typically [prefer] an amber, fire-lit ambience because it tends to put people at ease – it psychologically reminds them of a fire or being warm and cozy. Now, [imagine] a blue light. Blue is not usually associated with a feeling of warmth, so [when customers] walk through a space illuminated with light sources containing more of the blue/green spectrum, such as fluorescents, [they might] think it [feels] high-tech or a little more modern, maybe a little colder. It’s another subtle way to affect your environment, without being too overt.”

That doesn’t mean soaking your store in bold hues is the solution – it’s paramount to remember that color isn’t interpreted the same way across cultures. In China, for example, the color red is usually symbolic of prosperity and luck, while in the U.S., it could be interpreted as danger or a warning.

“It can totally change someone’s outlook to step into a space that’s bathed in a certain color. It will change their emotion, and whether that’s for better or worse depends on the individual,” says Jill Klores, founder, owner, Essential Light Design Studio LLC (Dallas), who emphasizes that a good control system is key to proper on-site color tuning.

Washing a store’s façade in color, whether rotating or static, is another common way to convey feeling – but it’s easily overdone.

“When color-changing lighting moved into architecture, everybody lost their minds, and before you knew it, every building was being lit with color-changing lights … I think we’ve already gone through a period of ‘I can’t take this anymore,’ when it comes to color-changing [lights],” says Kathy Pryzgoda, owner and principal designer of Culver City, Calif.-based Light Studio LA, who explains color should primarily support the brand’s image.

That doesn’t mean up-lighting exteriors is a bad move, but step lightly.

“With one of the clients we’re working with now, we might light the store interior with 3500 or 3000 Kelvins, [but] we’re lighting the façade with 2500,” says Andrew McQuilkin, retail market leader, BHDP Architecture (Cincinnati). “We’re trying to [convey] a building that’s much warmer and inviting from the road.”

Color temperature and actual color are two different things: In layman’s terms, color temperature is measured in Kelvins and denotes which part of the color spectrum is found in a light source. That means temperatures greater than 5000 Kelvin are considered “cool” colors (appearing bluish white), while Kelvin temperatures between 2700 and 3500 are considered “warm” (appearing yellowish white and red). 

Pryzgoda says she’s noticed an increase in cooler color temperatures due to “technology forcing us away from the incandescent source.” It’s because of perception, she says, as the stores she’s working with have begun favoring cooler temperatures to make in-store colors and elements pop. “We’re going to shift in terms of 2700 Kelvin as the standard, and I believe 3000 or 3500 Kelvin is becoming the new warm light,” Pryzgoda says.

Cooler temperatures can be a positive attribute with signage. “When you go cooler, graphics and edges of graphics are a lot easier to see,” says McQuilkin. “If I’m designing a store that’s going to have a lot of hard product or packaging, I’m going to lean toward cooler [because] graphics [appear] crisper and brighter.”

Tunable white LEDs, while not yet widely used, might hold the key to adjusting ambience on the fly. Some light fixtures reportedly allow users to adjust the temperature from 2700 to 5000 Kelvins with the push of a button or twist of a dial.

That means stores could adjust their lighting to complement the time of day, instead of keeping employees and customers in a static environment.

“During the day, we could tune it to cool to match the sunlight, and at night, we’d tune it down to warm,” Pryzgoda says. “If it’s warm, our perception may be that [the lighting’s] not bright, but it’s not actually dimming the light, it’s just changing its color.”

“Flicker is a topic that should be widely discussed. It’s a problem,” says Klores. “Usually at 100-percent output, things are stable. As soon as you start dimming [a light source,] you can run into problems if you don’t have good compatibility between your LEDs and your dimmer, or your LEDs and driver.”

While dimming isn’t widespread in retail, LED flicker is still a threat. And though LED technology has been around for many years, the kinks are still being worked out, according to Lew, “LEDs are sort of like the ‘Wild, Wild West’ of lighting design. We’re learning about the technology at the same time we’re required to implement it into a project to comply with new energy standards.”

Lew explains that incandescent bulbs have a naturally smooth dimming arc, where the illumination seamlessly shifts toward a very warm amber at lower illumination levels without noticeable flickering. LEDs do not yet possess that quality at dimmed illumination levels, Lew says, so the advances in technology are trying to emulate that flicker-free, warm dimming curve with LED sources.

“It’s all about the driver,” says Pryzgoda, who explains that manufacturers and suppliers are more inclined to specify which driver should be paired with various types of LEDs. “Are we there yet? No. Are we getting there? Each month we’re seeing better product. But in retail, the good news is we’re not dimming – yet!”

The question remains: Do various types or colors of light affect moods and circadian rhythms in a retail environment?

The answer is yes, but it may be more advantageous to design for circadian benefit with sales associates in mind – for those who are exposed to the environment all day, versus customers that have variant dwell-times.

“It’s about the cycle of light,” Klores says. “We, as humans, have grown up with light cycles throughout the day – its [levels of] intensity [and] color. [It would be great to] provide some of that to employees who are inside for 8 hours and not getting any variation whatsoever.”

Klores suggests installing cooler color-temperature lighting in an employee break room so that, over the course of a day, workers are exposed to sources that support the circadian rhythm of day-adapted individuals; brighter, cooler color-temperature lighting can suppress melatonin production. And for employees who receive no daylight at all, Klores says, lighting with a shifting Kelvin temperature could also be beneficial. For interior mall locations, advancements in sensor technology (like the ones used for daylight harvesting) could potentially control a store’s light settings throughout the day, without someone having to physically see the brightness level outdoors, Klores says.

Full-spectrum LEDs, which are currently making an impact in the healthcare industry, may soon provide similar benefits in the retail world, according to McQuilkin, whose firm uses the technology in laboratory settings, where workers are inside 8 to 12-or-more hours per day without sunlight.

“A customer could be shopping for an hour or two and get back outside, but if you’re in a store 8 to 10 hours per day – and in winter, you get up, it’s dark, and when you go home, it’s dark – it wears on you,” McQuilkin says. “You could end up having happier employees, which means more sales.”

It’s a win-win.