Blinding Headlights

I’ve lived in Tucson, Arizona for ten months now, and I have to tell you, it is no fun driving here at night. While it is a joy living in a city that for a change isn’t horribly overlit and that takes light pollution seriously (though that is starting to erode), it is often hard to see at night because of the many vehicles on the road with blinding headlights. In recent years, this has become a huge problem throughout the U.S., and the National Highway Traffic Safety Administration (NHTSA) and the Insurance Institute for Highway Safety (IIHS) needs to act quickly and decisively to deal with this dangerous nuisance.

Not only have headlights gotten brighter and bluer (which makes glare much worse), many vehicles have multiple sets of headlights, including “fog lights” that are anything but. High-profile vehicles such as pickup trucks and SUVs are especially bad when it comes to causing blinding glare for smaller, less extravagant vehicles. Jacked-up pickup trucks are the worst, and there are a lot of them here.

When one of these headlight-offensive vehicles is heading towards you, it makes it difficult to see the road ahead. It is especially hard to see pedestrians and bicyclists. Pavement markings are also harder to see because of the glare from the oncoming vehicle, especially when those lines are badly faded and in need of re-painting (as they often are here).

Tucson has far too many busy intersections without a protected left turn, and if you find yourself in a left-turn lane being stared down by a headlight-offensive vehicle in the opposite left-turn lane, the glare blinds you so much that it is difficult to see oncoming vehicles in the through-traffic lanes.

When a headlight-offensive vehicle comes up behind you and, as they often do, practically rides your bumper because driving at or near the speed limit isn’t fast enough for them, you’re hit with their intense glare in all three rear-view mirrors. This makes it harder to see the road ahead, and you have to slow down—which tends to aggravate them more than they already are. If you’re lucky, they can pass you—though sometimes they will illegally cross a double yellow line to do it.

Because of all these intense and unregulated vehicle headlights, I now avoid driving at night whenever possible.

Sure, headlights like these helps the perpetrator see better so they can drive down the road at night exceeding the speed limit (which is seldom enforced here, by the way), but everyone else—drivers, bicyclists, and pedestrians—is blinded.

What are the specific problems with modern vehicle headlights that need to be addressed, and what are the solutions?

  • Problem: The average vehicle’s total headlight lumen output (and individual headlight luminance) has dramatically increased in recent years, causing a corresponding increase in discomfort and disability glare for everyone else.
  • Solution: Headlights would not have to be so bright if speed limits were lower at night on many city streets and thoroughfares, and if the posted speed limits were actually enforced.
  • Solution: Implement adaptive driving beam (ADB) technology that uses sensors to detect oncoming traffic and adjusts the projected beam pattern to allow plenty of light for the driver without blinding other motorists. (ADB is widely used in Europe, but is not yet legal in the United States.)
  • Problem: Light-emitting diode (LED) and High Intensity Discharge (HID) headlights emit more light at the blue end of the visible spectrum than traditional warm-white or yellowish halogen headlights do, and these bluer lights result in significantly greater visual discomfort and impairment for other drivers.
  • Solution: Limit the amount of blue light that headlights can produce.
  • Problem: Poor headlight aim leads to dangerous glare for others.
  • Solution: Require regular headlight aim inspections and adjustments. Anytime a vehicle’s suspension is lifted, require headlight aim to be adjusted downward accordingly.

Here’s a petition you might want to sign:

https://www.change.org/p/u-s-dot-ban-blinding-headlights-and-save-lives

I’d like to close this article by quoting one of the many insightful comments in the Comments section of the New York Times article listed under References below.

Like everything else, it is no longer about the collective good and the laws that protect it. Individualism now rules—individual freedom. Headlights have become a First Amendment issue—an element of free speech.

And they have become part of the conservative anti-government backlash. Laws regulating headlights are seen as government intrusion into personal freedoms. It is seen by many to be like the COVID mask issue. Too many people think personal freedom trumps everything else–even collective health and safety.

And there is a free-market aspect to this. Manufacturers are looking for ways to add features to cars that will make them more attractive to buyers. They know the lights are unsafe, yet they put them on their vehicles.

America has lost all common sense.

Michael
Evanston, IL | June 9, 2021

Mark my words, if we keep heading down this path of excessive individual freedom (read: selfishness) without significant responsibility for the common good (that means everybody, not just your tribe), it will be our undoing. The United States will become a miserable place to live for the majority of us for at least a generation. I’m not hopeful that we can turn this around in time. Too many of us are “asleep at the wheel” and too easily swayed by misinformation and propaganda.

References

Mele, Christopher. “Blinded by Brighter Headlights? It’s Not Your Imagination.” New York Times, June 5, 2021, https://www.nytimes.com/2021/06/05/business/led-hid-headlights-blinding.html.

Blue Light Blues

One by one, all of our warm white lights are being replaced by cold, harsh, bluish-white LEDs.  And it is happening fast.

Everywhere.  In our streetlights, our workplaces, even our homes.  How do you like looking into those blue-white vehicle headlights as compared with the yellow-white ones we have been using since the automobile was invented?

LED lighting is the way of the future, don’t get me wrong, but we should be specifying and installing LED lights with a correlated color temperature (CCT) of 2700K or 3000K—with few exceptions—not the 4000K or higher that is the current standard.

Why is 4000K the current standard?  Because blue-white LEDs have a slightly greater luminous efficacy than yellow-white LEDs.  Luminous efficacy is the amount of light you get out for the power you put in, often measured in lumens per watt.  But should luminous efficiency be the only consideration?  What about aesthetics?  In addition to luminous efficacy, there are other, more significant ways to reduce power consumption and greenhouse gas emissions:

  • Use the minimum amount of light needed for the application; no need to overlight
  • Use efficient light fixtures that direct light only to where it is needed; near-horizontal light creates annoying and visibility-impairing glare and light trespass, and direct uplight into the night sky is a complete waste
  • Produce the light only when it is needed through simple switches, time controls, and occupancy sensors; or, use lower light levels during times of little or no activity

Even the super-inefficient incandescent light bulb (with a CCT of 2400K, by the way), operating three hours each night uses less energy than the light source with the highest luminous efficacy operating dusk to dawn.  Think about it.

In my town, as in most now, the soothing orange 1900K high pressure sodium (HPS) streetlights are being replaced with 4000K LEDs.  That’s a big change.  It will completely transform our outdoor nighttime environment.  Warm-white compact fluorescents are 2700K, and even tungsten halogen bulbs are 3000K.  Do we really want or need 4000K+ LEDs?

We are currently witnessing a complete transformation of our illuminated built environment.  Not enough questions are being asked nor direction being given by citizens, employees, and municipalities.  The lighting industry generally wants to sell as many lights as possible at the highest profit margin.  We as lighting consumers need to make sure we have the right kind of light, the right amount of light, and lighting only when and where it is needed.

Higher color-temperature lighting of 3500K or higher is often specified for office lighting during the day to more closely match daylight color temperature, but all to often this type of lighting is also being specified for nighttime use.  Lower color temperature lighting of 2700K or 3000K should be used for residential lighting and any other lighting that is primarily being used after sunset, such as streetlighting, parking lot lighting, and security lighting.