AMA Issues LED Streetlighting Guidance, Controversy Ensues

Street and area lighting are among the most popular applications for LED sources. It’s estimated that more than 10% of streetlights have been converted to LED technology in the U.S.

Many LED streetlights exhibit characteristics that are very different than traditional high-pressure sodium sources. The popularity of LED streetlighting led the American Medical Association (AMA) to issue community guidance to communities installing it.

While acknowledging the benefits of LED streetlighting, AMA cautioned against possible health and safety impacts, notably resulting from poorly designed “high intensity,” blue-rich lighting.

“Despite the energy efficiency benefits, some LED lights are harmful when used as streetlighting,” says AMA Board Member Maya A. Babu, MD, MBA. “The new AMA guidance encourages proper attention to optimal design and engineering features when converting to LED lighting that minimize detrimental health and environmental effects.”

AMA advised communities to:

* Use LED lighting that minimizes blue spectral content
* Use sources that are 3000K CCT or lower
* Use luminaires that are properly shielded to prevent glare
* Consider dimming during off-peak operating times

Click here to download the AMA guidance (registration required).

Some AMA statements resulted in instant controversy.

The Illuminating Engineering Society issued a statement that said: “Of primary concern to the IES is the potential for this report and its ensuing press to misinform the public with incomplete or inaccurate claims and improper interpretations. We intend to respond to this through a proper analysis.”

IES added it hopes to work with AMA to ensure any lighting recommendations involve discussion with the IES.

Click here to read the IES response.

The Lighting Research Center issued a statement that included these key points:

* InGaN LED sources have greater potential than HPS to suppress melatonin (the hormone that regulates sleep-wake cycles)
* However, the amount and duration of exposure must be known before saying InGaN LED sources affect melatonin at night
* CCT alone is not enough to characterize the effect of a light source, in fact it’s misleading as it’s not really designed as a light and health metric
* Glare is mainly determined by amount and distribution of light entering eye, not light’s spectral content

Click here to download the LRC response.

The U.S. Department of Energy responded by stating there is nothing inherently dangerous about LED streetlighting. LED sources, in fact, offer advantages such as precise optical control, tailored spectral content and relative ease of dimming.

“Some media coverage can give the impression that LEDs are the enemy when in fact they’re a critical part of the solution, which the AMA acknowledges,” says Jim Brodrick, SSL Program Manager, DOE. “The key takeaway from the AMA’s guidance is the importance of properly matching lighting products with the given application, no matter what technology is used. More than another technology, LEDs offer the capability to provide, for each application, the right amount of light, with the right spectrum, where you need, when you need it.”

Click here to read the DOE response.

NEMA also responded:

* AMA guidance aligns with industry recommendations for lighting controls, proper source shielding, and minimizing light levels and energy necessary for the task
* AMA recommendations for spectral content is problematic–it is one factor, and a single solution is not effective for all applications

“The AMA recommendation encouraging the use of 3000K correlated color temperature (CCT) or lower may compromise the ability of the lighting system to meet all critical design criteria for each unique application,” NEMA stated. “As indicated by the U.S. Department of Energy (DOE) in its June 21, 2016, statement, CCT does not explicitly characterize the potential for nonvisual effects, which also depend on quantity and duration of exposure to light. The DOE further clarifies than an LED light source with the same CCT as a non-LED source has about the same amount of blue spectral content. The AMA recommendation for 3000K or lower is not an appropriate solution for all applications, nor is it is supported by the current body of research. NEMA will issue additional technical guidance specific to the issues and tradeoffs related to the spectral content of lighting solutions.”

Click here to read the NEMA response.

My take:

It appears the AMA is well-intentioned here and raising some legitimate concerns, though their conclusions are questionable based on the research, and their solution may be oversimplified. They should consult the lighting industry on any lighting guidelines. IES has said it will contact AMA and seek to represent the lighting industry on lighting-related guidelines, which is very positive. As the lighting industry has been talking about light and health for some time, I’m surprised that link doesn’t already exist.

But even that would not have solved one of the biggest problems here, which is media ignorance about lighting and constant need to quickly and simply convey a story, which results in misleading instead of informing. In my opinion, IES needs to go even further to ensure that if the AMA sends a press release, that release not only promulgates guidelines IES endorses but also puts forward one or more lighting experts who can talk to the media and represent the lighting industry. These experts would get some type of media training.

5 Comments

  1. Barry Howard says:

    Though Well Intentioned the AMA did not rely on very good data to really explain the issues.

    There is very good Data on Phase Shifts occurring from Light Sources produced from exposure to combinations of intensity and CCT and keys in on 480 Nm Range. The Netherlands, Germany, and Norway are providing guidance based on reasonable Science which I feel certain IES has been apprised of.

  2. The LED is a relatively new light source. This new source requires new thinking and therefore new criteria for lighting streets and lighting roadways. There is a difference. In many cases this has not occurred and the resulting lighting has not been well received by the neighborhoods where they were installed.
    I have used miles of LEDs on some projects but have used large scale mockups to determine if their use was appropriate. More work is needed.

    I am glad to see the AMA entering the discussion. It is a fresh and unprejudiced contribution to the use of this new source.

    There is an interesting set of negative feedback circulating in Europe which should be looked at in the ongoing use of this new source. It has the potential to advance lighting practice. Let’s do what is required to get it right.

    Howard Brandston

  3. Craig Oty says:

    Sadly, the first paragraph on the CNN article gets CCT wrong:

    “The American Medical Association (AMA) has just adopted an official policy statement about street lighting: cool it and dim it.”

  4. Bob says:

    UV and Skin Cancer…Cancer and second hand smoke…global warming…

    These examples and others like them were, and some still are, denounced as folly by industries directly affected financially by science. One can always debate and take a position of opposition for the betterment of themselves, which is tradition.

    Time will add to the discussion of truth or not. However, the hope is that industries and manufactures will keep an open mind on such topics.

  5. Bill Swanson says:

    I have a lot of problems with this. The study confuses correlation and causation. People in urban areas get a little less sleep every night and the quality of sleep is lower. Urban areas have brighter streets. Therefore the street lights must be the cause? You could just as easily blame higher CO2 levels, more particulates in the air, louder noises, more feral cats, etc. This study does not show any link that blue light in street lights are disrupting people’s sleep. This study doesn’t even show the amount of blue light in the cities studied.

    The claimed link to cancer is also doubtful. There was a study a few decades ago that showed nurses working night shift had a higher rate of breast cancer. I can believe this one. Their circadian rhythm was all messed up and it likely messed with a lot of stuff in their bodies. This study referred to nighttime lighting as the cause. Now, most people read nighttime lighting and think exterior lights, but this study was on nurses working indoors. Nighttime lighting was meant as lighting they were exposed to at night.

    The poison is in the dose. Interior lighting is often at around 50fc for nursing areas. Parking lots and roads are typically lit to an average of 1 fc. The length of exposure is different too. 8 to 12 hours a night at 50fc vs maybe 1 hour at 1fc. That is 0.25% of the exposure level. Why is the AMA worrying about exterior lighting when they should be focused on interior lighting for people who work night shift.

    Currently, the Illuminating Engineering Society (IES) and the Lighting Research Center (LRC) say more research is needed before making recommendations about the impact of blue rich exterior white light.

    My own opinion is that someone is making a mountain out of a mole hill. Metal Halide lamps have been used for decades and are also blue rich light. LED’s are new, and new stuff seems to scare people.

    I complained about the “cool it and dim it” phrase being incorrect on another article. The author snapped at me regarding the Kelvin temperature. Author Richard Stevens wrote, “Use of ‘cool’ to mean higher color temperature is strictly jargon in the lighting design community; it has no objective basis and is used because lighting people think high CCT lights ‘look’ like ice, or something. To me they look like the blue flame of an acetylene torch. In English, ‘cool’ means lower temperature, and I was writing for people who speak English.”

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