What is the purple-bluish glow coming from some lights above Western Pennsylvania highways?

There’s a purple-bluish glow coming from some of the lights above highways in Western Pennsylvania.

It’s a bizarre look. What’s causing it, and is anything being done to address it?

Chief Investigator Rick Earle noticed the phenomenon while driving on some local roads and went to PennDOT to get to the bottom of it.

Earle noticed that nearly a dozen highway lights at one particular location are purple or bluish, instead of the traditional white. At first, he suspected PennDOT may be testing some new lights.

He also spoke with drivers who noticed the lights but had no idea what was going on.

“I have noticed some weird colors. I didn’t know what was going on,” said Danny Soisson, who lives in Youngwood just down the street from the purple lights.

Some drivers were caught off guard by the gauntlet of the purple bluish glow from the lights along this highway in Westmoreland County.

“I see blue, so I definitely noticed the different color of the lights,” Soisson said.

It’s happening at the intersection of Toll 66 and Route 119 near New Stanton, where you can clearly see the different colors from at least ten highway lights.

“I don’t know whether it was to keep bugs away or what. I’m not sure,” Austin Perry said.

“I keep looking for cameras to see if any cameras [are] attached and hanging up there as well with them to see if they are looking for reaction or whatever they’re looking for,” Soisson said.

One driver told us he thought a police officer had pulled in behind him when he passed the lights.

“I have seen the purple lights. They actually are about two and half miles from my house, so I noticed them last summer,” said Rachel Duda, PennDOT District 12 Executive in Uniontown.

Duda lives in Brownsville, and that’s where she first noticed the purple lights.

“There’s all kinds of conspiracy theories as to why the lights are purple, if it’s done on purpose,” Duda said.

But 11 Investigates discovered that PennDOT is not testing new lights, no cameras are attached and it’s not for bugs.

The LED lights, Duda told us, are defective, causing the purple bluish hue.

“It’s really just a defect in the LEDs where the blue light comes through because there’s a layer that gets rubbed off in time over the LED cells that causes the purple light to shine through,” Duda said.

11 Investigates found out how the lights go from white to purple.

According to lighting experts, the inner core of the LED is a blue chip.

It’s coated with a layer of yellow phosphor, so it emits a white light.

But in the faulty lights, that coating of yellow phosphor is wearing off, causing the purple bluish hue.

Experts believe a poor coating process is the main culprit, but they said heat and vehicle vibration may also have an impact.

Duda, who runs the Uniontown office, is aware of three locations in her district.

They are Route 119 near New Stanton, which we told you about, along with Route 40 near Brownsville and Route 31 in Donegal.

District 12 covers Westmoreland, Fayette, Greene and Washington counties.

11 Investigates also found some of the faulty lights in Allegheny County, and we discovered it’s happening across the country.

At least 31 states have seen the defective lights.

Some drivers we spoke with clearly noticed the difference in brightness.

Earle: Is it a little darker, a little more difficult to see in those areas. Did you notice that?

Perry: During nighttime, I guess. You got to be cautious with cars in general.

Earle: The lights not as bright as the white light.

Perry: No, no.

But PennDOT Executive Duda said so far, the defective lights, which are supposed to last longer than the standard high-pressure sodium lights, haven’t caused any safety concerns.

“We have not seen any evidence that they cause any safety harm, or they’re ineffective because they still do produce some lights. There haven’t been any increase in crashes at those locations,” Duda said.

The defective lights are approximately six years old, and no longer under warranty.

They cost $500 to $600 each.

PennDOT said they plan to replace them soon with LED lights they hope will last a little longer.

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