I recently had the pleasure of interviewing Scott Roos, Vice President Product Design, Juno Lighting Group (Acuity Brands). The topic: lighting and health. I’m happy to share his responses with you here. The interview informed an article I wrote for the August 2016 issue of tED.

DiLouie: What do we currently know with a fair degree of certainty about the relationship between light and health?

Roos: We know with certainty that for normal populations exposure to blue rich light during the day supports optimal circadian health, and exposure to blue rich light at night disrupts our circadian rhythms with negative consequences for sleep and health.

DiLouie: What don’t we know yet? What research is being done to gain this knowledge, and how might it affect lighting practice?

Roos: Our knowledge of how specific wavelengths, doses and exposure times impact our various biological, physiological and behavioral systems and how these can be effected by personal factors such as age, caffeine consumption or specific health conditions, while increasing, is still limited. Numerous research studies continue to be conducted by both the public and private sector. As these research results along with early adopter applications come online with evidence- based results, our knowledge base and ability to provide more concrete recommendations for lighting practitioners will continue to increase. The most comprehensive listing of research in this field can be found on the Lighting Research Center website http://www.lrc.rpi.edu/programs/lightHealth/research.asp. It is also important to understand that the study of light and health is a subset of a larger emerging field of study known as circadian medicine, of which light exposure is an important, but not the only component.

DiLouie: The relationship between light and health is now turning into a conversation about best practices related to lighting design and health. What can the lighting industry definitively claim at this time?

Roos: First, there is no substitute to being exposed to natural light. Taking time in the morning and during the day to go for a walk may sound simple, but it is probably the best way to optimize your circadian entrainment. Likewise, there are numerous studies going back many years that show how day lighted interiors with a view support health and well-being.

Second, during the day when indoors, while we may not know everything about how the exact spectra and amount of artificial lighting effects our health and wellbeing, for normal populations you probably can’t have too much illumination or too cool of a color quality of light. Typical indoor artificial illumination is much warmer and at much lower levels than what we experience outdoors.

Third, at night minimize both the amount and the blue content of light.

And fourth, recognize that negative lifestyle habits, including using self-illuminated devices at night, can negate the impact of even the best thought- through interior circadian-sensitive lighting plan.

DiLouie: How do you feel about where the industry is currently going with this? Do you think we’re getting it right? Where are we getting it wrong? How close are we to an industry recommended practice?

Roos: The “typical” lighting scenario of working in a cool, brightly illuminated office during the day and a warmer, more dimly illuminated home environment during the evening is actually spot-on in terms of supporting good circadian health for normal populations. We are starting to characterize the circadian content of various light sources, which is different than the visual amount of light as measured in lumens or footcandles. Understanding this will help us do a better job selecting the most efficient light source in terms of either eliciting a circadian response during the day or preventing it at night. And optimizing the circadian content of a lightsource will allow us to stimulate a circadian response with lower levels of illumination, which will address the concern over having to using more energy for circadian lighting installations. As we continue the migration toward LED technology we will have more refined ways to optimize the quality and amount of light both during the day and at night.

For example, we can now spectrally tune LEDs both to insert or remove blue content and can specify warm dimming as an option on an increasing array of luminaire types. As far as IES recommended practices on Light and Health, while we can reasonably expect to start seeing references made to this subject in various publications, including the soon to be updated IES RP-29 Lighting for Healthcare Facilities, specific recommendations are still several years away. It is one thing for someone like myself who follows this topic to express opinions based on reviewing research, presentations and having discussions with leading experts. It is yet another for an industry organization such as the IES to publish recommendations that need to be based on exacting research and evidence-based results. By the time these are available I expect that the basic principles of healthy circadian lighting for normal populations will already be widely understood. The biggest impact that the recommended practices will likely have is on the nuanced use of lighting for non-normal populations such as shift workers, less mobile elderly in extended care facilities and people with specific health conditions.

DiLouie: In healthcare environments, what role can lighting play in facilitating well-being and enhancing the treatment and healing process?

Roos: The answer to this question contains both simple and complex components. The simple components involve providing as normal of an exposure to simulated day/night quality and cycles of illumination for the benefit of the patients. The medium complexity issues are how to best keep healthcare night shift workers alert, productive and less error prone while supporting their circadian health. And the most complex aspect of this, relating to enhancing the treatment and healing process, will be borne out of the growing body of research where scientists are studying the effect that different spectra, amounts of light, exposure times and time of day that exposures are administered have on various medical conditions and the efficacy of the plethora of pharmaceutical treatments.

The first issue can be addressed by the lighting practitioner with a modest bit of research and education. The second issue can be addressed by the lighting practitioner in cooperation with experts on 24/7 work environments and circadian health. This likely will entail both the specification/installation/commissioning of a given lighting system and ongoing monitoring of shift workers’ biological markers with real-time feedback to adjust the lighting system as needed. And the third issue will fall mostly outside the scope of a lighting practitioner and into the domain of a healthcare professional. The lighting practitioner may be directed to specify a given luminaire, likely listed with the FDA as a medical device, with a given set of capabilities and be responsible to place the fixture(s) such that their location and interaction with room surfaces optimizes the amount of light actually reaching the patient’s eyes. But a healthcare professional will be responsible to select the exact spectra, amount, timing and duration required for a given patient.

DiLouie: What are the benefits for owners of commercial lighting systems for giving design priority to lighting that is conducive to circadian health?

Roos: While still very early in the adoption cycle there is a small, but growing body of early-adopter applications that are demonstrating that the principles of optimized circadian lighting as proven in laboratories can indeed improve an occupant’s productivity, health, sleep and emotional well-being. This applies across a wide range of applications ranging from sports team locker rooms, classrooms, special education facilities, extended care facilities offices and 24/7 industrial operations. Each different application will yield its own set of benefits for which the building owner can decide if it is worth the extra effort and cost to achieve. For a school it might be higher student achievement/attendance. For an office it might be higher employee productivity & morale, reduced sick days/medical claims and lower turnover. For a healthcare facility it might be quicker patient healing times, improved health & attendance of night shift staff with a lower rate of errors. And in a 24/7 industrial it could be improved worker safety, performance and attendance.

DiLouie: What should electrical distributors be doing at this time to properly promote and sell lighting solutions that are conducive to health?

Roos: The biggest thing that an electrical distributor can do at this point in the adoption cycle is to educate themselves such that they can at least bring up the opportunity and benefits that optimized circadian lighting can have, on top of basic energy savings, to their clients, and then position themselves to partner with independent consultants and knowledgeable manufacturers to help them recommend and implement the best solutions. Also, it is important to be able to recognize and point out situations that can be especially detrimental if circadian lighting principles are not adhered to. For example, if you are working on project to light classrooms or lecture halls that will be used both during the daytime and evening, you owe it to your customer to make them aware that providing blue rich light in a classroom at night can negatively impact student performance and well-being. Or, if you are lighting an extended care facility consider recommending that your customer work with an expert to optimize the lighting such that it will significantly improve the physical and emotional health and social integration of residents, help improve the working conditions for staff and likely lower the cost of care.

DiLouie: If you could tell the entire electrical industry just one thing about lighting and health, what would it be?

Roos: The whole field of circadian medicine, which includes circadian lighting, is an emerging field that is poised to have a monumental impact on human health, well-being and productivity. It will increasingly effect preventive health, medical treatment protocols and guide how we light our daytime and nighttime environments. Like any new field it likely will take a decade or more to become mainstream, but that creates a great opportunity for you to lead your organization into this emerging field and create your network of experts that allows you to step into a non-commoditized “blue-ocean” field and differentiate yourself in your served markets. Don’t take my word on it…do your own research, starting with the information posted on the Lighting Research Institute and Human Centric Lighting web sites, and form you own conclusions.