Fly into any major city at night and you’ll notice vast swaths of bright white lights replacing the yellow hue from high-pressure sodiums, once the preeminent lord of night lighting across the urban fabric.
The white light is from LEDs - light emitting diodes - and cities are installing them in an implementation tsunami. They are cheaper and they are brighter, but I have been bothered by their excessive glare and, during our night site visits, I always warn students about the lack of research on LED and human behavior. Over the years I’ve blogged about sodiums and Randy Atlas has guest blogged here on LEDs. But research has been scant.
Until now! And the early results are worrying.
AMERICAN MEDICAL ASSOCIATION
The American Medical Association has released a statement condemning the health effects of LED street lighting.
The AMA identifies two concerns:
Obviously, the AMA studies are not the final word. For example, the blue from LEDs can be controlled.
The lighting industry, understandably, is not happy with the AMA conclusions. One source says “As with any new technology, there are a lot of unknowns that only time will be able to tell what the results/answers will be.”
That is the same thing we have been saying about LED lights from the beginning. In the budget-saving rush to install LEDs we know very little about the behavioral, social and medical consequences from these new light technologies.
Students of CPTED know that lighting research regarding safety is based on quantity, not quality. I have yet to read a single study on light source quality and crime related behavior. This knowledge gap isn't limited to LEDs, we also have inadequate qualitative information on halide or sodium light sources.
Until we do, it’s probably best to look for successful cities with exceptional lighting, such as Melbourne, Australia, and see what they do right.