Avoid Blue-Rich LED Lighting

As Dodgeville (and many other towns and cities) are planning to replace their streetlights with LED luminaires, it is imperative that we use LEDs with a CCT (correlated color temperature) of 3000 K or less (Jin et al. 2015).  This is a “warm” white light (similar to incandescent) rather than the “cold” blue-rich light often seen with LEDs.  Outdoor LED luminaires often come in at least three “flavors”: 3000K, 4000K, and 5000K.  For example, American Electric Lighting’s Autobahn Series.  5000K luminaires provide the bluest light, and should be avoided at all costs.  Of these three, 3000K would be best, and if 2700K is offered, use that.

Why does this matter?  On June 14, 2016, the American Medical Association issued guidance on this subject.

High-intensity LED lighting designs emit a large amount of blue light that appears white to the naked eye and create worse nighttime glare than conventional lighting.  Discomfort and disability from intense, blue-rich LED lighting can decrease visual acuity and safety, resulting in concerns and creating a road hazard.

The detrimental effects of high-intensity LED lighting are not limited to humans.  Excessive outdoor lighting disrupts many species that need a dark environment.  For instance, poorly designed LED lighting disorients some bird, insect, turtle and fish species, and U.S. national parks have adopted optimal lighting designs and practices that minimize the effects of light pollution on the environment.

Recognizing the detrimental effects of poorly-designed, high-intensity LED lighting, the AMA encourages communities to minimize and control blue-rich environmental lighting by using the lowest emission of blue light possible to reduce glare.  The AMA recommends an intensity threshold for optimal LED lighting that minimizes blue-rich light.  The AMA also recommends all LED lighting should be properly shielded to minimize glare and detrimental human health and environmental effects, and consideration should be given to utilize the ability of LED lighting to be dimmed for off-peak time periods.

Incidentally, for your residential lighting needs, a good local source for LED bulbs that are not blue-rich is Madison Lighting.  They have many LED bulbs in both 3000 K and 2700 K. I use 2700K bulbs exclusively in my home, and the warm white light they provide is an excellent replacement for incandescent and compact fluorescent bulbs.  Never purchase LED lighting without knowing the color temperature of the lights.

If you’re skeptical that the color temperature of LEDs is an important issue, I suggest you purchase a 2700K bulb and a 4000K or 5000K bulb with the same output lumens and compare them in your home.  I believe that you will much prefer the 2700K lighting.  If 2700K lighting is best for your home, then why should it not be best for outdoor lighting as well?

Besides, most streetlighting is currently high pressure sodium (HPS), which is inherently non-blue-rich.  You will find that 2700K LED lights offers better color rendering than HPS without the need to go to even bluer lights.

If you have ever been irritated at night by an oncoming vehicle with those awful “blue” headlights, you’ve experienced firsthand why blue-rich light in our nighttime environment must be minimized.

Why are 4000K and 5000K LED lights so prevalent?  They are easier and cheaper to manufacture, but with increased demand of 2700K and 3000K LED lights, economies of scale will reduce their cost, which today are generally slightly higher than blue-rich LEDs.

Now, a bit more about why blue light at night can be detrimental to human health, and the primary reason why the AMA issued a guidance on this subject.

In addition to image-forming rods and cones, there exist non-image-forming retinal cells in the human eye called intrinsically photosensitive retinal ganglion cells (ipRGCs) that help regulate our circadian rhythms.  Studies have shown that blue light is far more disruptive to our circadian rhythms than redder light (Lockley et al. 2003).

Now, on to the environment.  Using a clever technique that compared sky brightness at several locations on several nights both with and without snow cover, Fabio Falchi (Falchi 2011) determined that at least 60% of light going up into the night sky is direct waste lighting, and 40% or less is reflected light.  This is as good an argument as any that we still have a long way to go towards using only full-cutoff luminaires that do not produce any direct uplight.  Blue light scatters much more in the night sky than red light, and this is due to Rayleigh scattering which tells us that the amount of scattering is proportional to the inverse of the wavelength of light to the fourth power, σs ∝ 1 / λ4.  This also explains why the daytime sky is blue.

Bluer wavelengths of light thus increase artificial sky glow to a much greater extent than redder wavelengths do.  Not only is an increase in blue light bad for astronomy, but its impact on the natural world is likely to be adverse as well.

Falchi recommends a total ban of wavelengths shorter than 540 nm for nighttime lighting, both outdoor and indoor.  He goes on to say that, at the very least, no more light shortward of 540 nm should be allowed than that currently emitted by high pressure sodium lamps, lumen for lumen.

Falchi, F. 2011, MNRAS, 412, 33
Falchi, F. 2016, The World Atlas of Light Pollution, p. 44
Jin, H., Jin, S., Chen, L., et al. 2015, IEEE Photonics Journal. 7(6), 1-9
Lockley, S. W., et al. 2003, J Clin Endocrinol Metab. 88(9), 45025

Our Vanishing Sidewalks

I’ll wager that most of you over 50 years of age grew up on a street with sidewalks on both sides of the street and all the way around the block.  You probably made use of them often.  Sidewalks used to be essential in residential neighborhoods.  Today, not so much.  More often then not, newer residential subdivisions do not have sidewalks, nor do they have off-road walking trails meandering through them.  If you walk at all, you have to walk in the street.  Having motorized vehicles and pedestrians sharing the same space is inherently risky, especially at night.

It is interesting to note that the Ancient Romans built sidewalks everywhere, but by the Middle Ages, people were again walking in the streets.  Progress is not inevitable.

Today, developers generally consider sidewalks to be an unnecessary expense, and homeowners are not clamoring for them because they are usually saddled with the expense of keeping them up.

Therein lies the problem.  It is my view that sidewalks should be treated as public infrastructure no different than city streets.  Just as the developer pays most or all of the cost of building the streets in a new residential subdivision, they, too, should be required to build sidewalks or, in a more rural subdivision, walking trails.  Sidewalks should be maintained (and that includes snow removal) by local government supported by tax revenues, not directly by the homeowner.

Perhaps the typical homeowner might be more supportive of sidewalks if they didn’t have to shovel the sidewalk in front of their house each time it snows, or replace sidewalk slabs when they’re broken or cracked.  Sure, they’d still be paying taxes to support those activities, but it would be a win-win situation for the entire community.  And shouldn’t that be our goal—the common good?

A Better Package

Expanded polystyrene (C8H8)n, known as EPS or styrofoam, consists of up to 98% air by volume, making it a great packaging material.  However, it is more difficult to recycle than other plastics and is also bad for the environment (floating in the oceans and ingested by marine animals, for example).  Expanded polystyrene in the form of packing “peanuts” and molded shapes has one very undesirable property for the end user: static electricity.  When you open a box with this material, the packing peanuts and detritus formed when you break larger pieces for disposal have a strong tendency to draw electrons away from other materials—even the air.  This results in a net negative charge, and EPS, being an insulator, ensures the excess charge remains localized and does not easily dissipate.  The result is that the EPS particles and peanuts stick to just about everything.  They also repel each other which often becomes a point of frustration when you try to corral the plastic peanuts in a garbage bag.

Fortunately, there is another option that is better for the environment and does not suffer from static electricity: starch-based packing materials made from corn or other plant materials.  You have undoubtedly come across cornstarch packing peanuts and maybe even noticed that they dissolve easily in water.  But did you know this material can also be shaped into molded forms and sheets?

I’d like to see “styrofoam” packaging materials completely replaced by starch-based alternatives.  Though currently these bio-derived materials are a little heavier than EPS and cost a little more to manufacture, with increased utilization and further research & development these current challenges can be overcome.

The next time you receive a package in the mail (or purchase an item at the store) from a manufacturer or a distributor that uses EPS materials, why not write them and ask them to use starch-based packaging materials instead?  And, be sure to thank manufacturers and distributors that are already using starch-based packaging materials.  As consumers, we have a responsibility to “move the needle” towards a more sustainable future for humanity on planet Earth.