The Benefits of Full-Spectrum Lighting?

Full-spectrum lighting is a hot trend, with manufacturers making claims that it improves concentration and learning among students, and more. For example, Full Spectrum Solutions Inc., a Jackson, MI-based lighting company that manufactures full-spectrum lighting products, says in a press release,“Independent studies demonstrate that ADD and ADHD can be managed and eliminated by simply improving the lighting sources in academic environments in which children study, learn, and grow. Children shouldn’t have to suffer from the unhealthy effects of poor lighting any longer. With Full Spectrum’s BlueMax™ Color Technology lighting, better grades and healthier children are just a light switch away.”

As the parent of a child diagnosed with ADHD, this writer sees three challenges with Full Spectrum’s claim. The first is that ADD and ADHD are one and the same. The medical community today refers to the disorder as ADHD, adding (per the patient’s diagnosis)“primarily hyperactive” or “primarily inattentive.” My son is ADHD, primarily inattentive. For credibility, Full Spectrum and other lighting manufacturers must eliminate redundancy and use accurate terminology.

The second challenge is that the press release doesn’t cite the independent studies for the reader to verify the accuracy of the claim that improving lighting sources in academic environments manages and eliminates ADHD. However, the firm’s Website,, does reference some studies and testimonials.

Third, ADHD is a neurological disorder for which, at this point in time, there is no cure. It simply cannot be eliminated by exposure to full-spectrum light. If it were that simple, then state governments would require that children be cured before attending school, just as they have to have the correct immunizations. And, if it were true, elimination of the disorder would be quite cost effective — simply take the children outside and expose them to natural daylight. Unfortunately, pediatricians, psychologists, psychiatrists, neurologists, pharmaceutical companies, and full-spectrum lighting companies would lose a lot of business.

That’s not to say that full-spectrum lighting doesn’t reduce ADHD symptoms. Maybe it does for some children. And maybe full-spectrum lighting has other benefits, too. Goodness knows this would appeal to both administrators and teachers, who require classroom order to accomplish teaching goals.

Upon doing some research on the benefits of full-spectrum lighting, it was discovered that this writer isn’t the only one questioning manufacturers’ claims. The National Lighting Product Information Program (NLPIP), the research arm of the Lighting Research Center (LRC) (, which bills itself as the world’s leading university-based (Rennselaer Polytechnic Institute, Troy, NY) research and education center devoted to lighting, has published an article titled “Full-Spectrum Light Sources.” The article was written Mark Rea, Lei Deng, and Robert Wolsey, and was last updated in March 2005. In it, the writers explore consumer perceptions about full-spectrum light sources and assess the validity of various manufacturers' claims.

Apples to Apples

What is full-spectrum lighting? “It replicates natural daylight without UV,” says Joelle Kolhagen, marketing director with Full Spectrum Solutions. “It’s the same type of lighting you get when you step outside.”

The article explains that the term “full-spectrum” was coined by photobiologist Dr. John Ott in the 1960s “to describe electric light sources that simulate the visible and ultraviolet (UV) spectrum of natural light.”

Further, says the article, the term “full-spectrum” is a marketing term implying a smooth and continuous spectral power distribution (SPD) without the spikes and troughs in radiant energy common with most discharge light sources (e.g., fluorescent and metal halide).

For the study, the NLPIP “reviewed the promotional claims for full-spectrum light sources from manufacturer and retailer Websites, and found a diversity of claimed benefits, including:

    • improves color perception,

    • improves visual clarity,

    • improves mood,

    • improves productivity,

    • improves mental awareness,

    • improves retail sales,

    • improves plant growth,

    • improves results of light therapy in treating seasonal affective disorder (SAD),

    • improves results of light therapy for sleep disorders,

    • improves scholastic performance of students,

    • improves vitamin D synthesis in the body, and

    • reduces incidence of dental decay.”

    Next, the NLPIP conducted a survey of lighting specifiers, asking, "Compared to other types of lighting, please indicate how you think full-spectrum light sources impact the following.

“Overall, the survey respondents believed in most of the claimed benefits of full-spectrum light sources,” reports the article. “The results of this survey indicate that the marketing message from manufacturers of full-spectrum light sources appears to be getting through to its intended audience of lighting specifiers.”

The next part of the article discusses the validity of the claims regarding full-spectrum light sources.

1. When it comes to color rendering, natural light has a CRI of 100 percent. Full Spectrum’s Kolhagen reports that the CRI on their products goes as high as 96 percent. The report writers agree that full-spectrum lighting provides excellent color rendering.

2. Regarding visual performance, the report states, “Full-spectrum light sources will not provide better visual performance than other light sources under most circumstances.”

3. Taking a look at health issues, the report concludes that full-spectrum light sources do not provide better health than most other electric light sources: “Light is the most important environmental stimulus for regulating our circadian cycles and synchronizing them to the solar day. Short wavelength (blue) light is particularly effective at regulating the circadian system; long wavelength (red) light is apparently inconsequential to the circadian system.”

Because the body is known to respond only to short wavelengths, light that maximizes short wavelengths would better maximize the circadian system efficiency than full-spectrum light, says Keith Toomey, director of communications for the Lighting Research Center. “I don’t want to give the impression that full-spectrum lights are terrible things, because they’re not. Who knows? With more research in the future, we may find that that body is affected by other wave lengths.”

4. Considering psychological benefits, the report states: “Full-spectrum light sources may have psychological benefits, particularly in societies that place value on ‘natural’ environments.”

Another part of the report tackles the cost issue, noting that full-spectrum lighting costs more than traditional kinds of lighting. “Full-spectrum lamps are often priced several times higher than conventional lamps. For example, in Troy, New York, a four-foot T12 lamp costs between $1.25 and $3.60, while a full-spectrum four-foot T12 lamp costs $14.90.”

Kolhagen doesn’t disagree that her firm’s full-spectrum lights cost more than conventional lamps, but does explain what you get for your money. “Administrators buy in large quantities, and that brings the price down,” she says. “We do try to work with our customers. Plus, our products are warrantied for two years. They’re all long life, which reduces maintenance costs. Some of our fluorescent tubes are rated at 33,000 hours.”

The report, however, takes the stand that full-spectrum lights are less energy efficient than more traditional lights: “Full-spectrum T12 fluorescent lamps have an efficacy about 30 percent to 40 percent lower than conventional triphosphor fluorescent lamps, and thus must consume more energy to provide comparable light levels.”

“The bottom line,” says Toomey, “is we don’t encourage school administrators to spend a premium on full-spectrum lighting because there is no clear evidence that they’re worth it.”

Advice for Administrators

At the end of the day, what’s a conscientious school administrator to do? He wants the best for his students and teachers, but he doesn’t have bottomless pockets; and he certainly doesn’t want to be taken for a fool. No doubt more lighting research needs to be done; unfortunately, that doesn’t help an administrator who wants to make a decision in the next year.

Kolhagen suggests thorough study to make the best purchasing decision. “Do as much research as you can,” she says. “Read up on it. Talk to people who’re using full-spectrum lights. I’ve heard testimonials from teachers and principals saying that it has really worked for their kids with ADHD. Give us a call; we can provide quotes that you might find useful in making a decision.”

Architect Joel Sims has an additional thought. An architect for 20 years and founder of, he suggests creating a prototypical classroom, especially for administrators who are considering a facility renovation or new construction. “All too often, we rush to do something, and we haven’t dealt with the prototypical model,” he says. “It really allows administrators the opportunity to evaluate the product. What do the teachers think? What do the students think? Then they can make a determination for themselves.

“It amazes me that people spend millions and millions of dollars on products that may not live up to their claims,” continues Sims. “It’s only sensible to spend the money to create one classroom, evaluate the outcome, and make changes from there.” Unfortunately, he notes, this prudent approach takes time, and administrators often are simply not thinking in this direction.

Next, Sims suggests another approach, as did Kolhagen: Visit schools that have installed full-spectrum lighting. Visiting a school, seeing the product and talking with people about it takes time, but it can be extremely beneficial. “Keep in mind,” he cautions, “that you can find people who will say something positive about anything.”

Ultimately, it certainly can’t hurt to give full-spectrum lighting a try. Nevertheless, administrators interested in reaping any perceived benefits owe it to the check-writer to carefully research and evaluate the product before choosing to buy.


A Purchasing Conundrum

“It seems like what’s happening now more than ever is that there are more products coming out because advances in technology provide the ability to create new products. The question is: How do we deal with that? Do we design a cutting-edge school with the new product only to discover that we spent too much money and haven’t gained the benefit? Or do we decide not to use the product because it isn’t proven and thus lose out on a good thing?”

Joel Sims