Nov 16, 2020

Flipping the script to focus on end-user outcomes

By Brian Liebel

Fifteen years ago, I wrote an article for LD+A entitled “The Quality Quandary.” That article focused on the visual aspects of lighting, with a seminal question as to whether the aesthetic quality of light is definable, and I resolved at that time to be content with the mystery surrounding our individual subjectivity; quality, I surmised, was in the eye of the beholder.

But now we have a challenge I can’t so easily dismiss. Our Society believes in quality of light, as expressed in our cause: “Improving life through quality of light”

What does this mean? How do we convey this belief in meaningful terms to decision makers who pay for the lighting systems we recommend, or to our partner organizations, or to society at large? How does IES make this statement more than words?

This requires us to do two things: First, we have to peel back the onion a bit on what we consider “quality of light”; no longer should it be limited to our subjective assessment of the visual world that light creates. Second, we need to reverse our approach to the question. For instance, the intuitive way of thinking about light quality is based on what looks better, what brings out an emotive response, or how light enhances the visual environment, leaving us with the “I know it when I see it” maxim without any quantitative way to assess real value to our clients. But what if instead we restructured the argument and asked what measurable improvements to life can be made that are attributable to light? And, if the improvement is due to lighting, wouldn’t we call that “quality of light?”

Let’s look at examples, and ask the question this way: What quantifiable improvements does a building owner want that could be effected through light?

INDEED, THE PHRASE “improving life” goes well beyond the personal experience of being ill or getting hit by a car; lighting systems have been the leader in energy reduction in buildings for 40 years and have provided a tremendous benefit to society through reduced power generation and electric grid security. Quality of light is also not limited to the physics of lighting quantity, or to color; we are rapidly gaining better understanding of the duration and time-of-day effects that make lighting controls a part of our qualitative equation beyond energy and aesthetics.

For every application, there are economic drivers for success that in large part are also improvements to the quality of life. When you start thinking of these as outcome-based objectives, it becomes very apparent that quality of light has great value; it’s up to us to determine how to model these benefits into engineering economics so that quality of light is also seen as a value of light.

The IES Standards and Research department is looking at this challenge through an analysis of outcome-based studies. Given all our lighting application standards, what are the economic drivers, and how might light effect life-improving outcomes? The construct for this is simple, and we know we don’t have all the answers, but taking this first step gives us a direction for discovering research in these areas, to see what work is being done that can offer insight quantifying quality of light through the lens of measured outcomes.

Building an analytic system for this approach will be a decade-long process, and that’s okay. We are identifying our objectives and laying out the variables. Through our advisory panels and technical committees, we are beginning this process now, and it promises to be a challenging and rewarding ride. Perhaps at some point, I’ll write a third article that will offer some resolution to this quality quandary.


Brian Liebel

Brian Liebel

Brian Liebel is IES director of standards and research. Prior to joining the IES, Brian was involved for nearly 25 years with research investigating the effects of spectrum on vision. He was chairman of the IES Visual Effects of Lamp Spectral Distribution Committee, the original... More info »