Drivers staring at cell phone screens or texting may not notice the brake lights on a truck they are following. The resulting collisions can be fatal.  -  Photo: Jim Park

Drivers staring at cell phone screens or texting may not notice the brake lights on a truck they are following. The resulting collisions can be fatal.

Photo: Jim Park

This industry is awash in safety regulations. It's odd to think that some of those rules actually stand in the way of improving safety and saving lives. So, when Oklahoma-based tank truck carrier Groendyke Transport decided to tackle the problem it faced from distracted drivers, it had to bend one of those rules. In doing do, it reduced its rear-end crash rate by more than 30%.

"We had to find a way to prevent people from running into the back of us," says Brian Gigoux, Groendyke Transport's vice president of equipment and maintenance. "We don't want to cause any problems for anybody behind this, but at the same time, we knew we had to get their attention."

While car-into-trailer collisions were nothing new to Groendyke, the number of collisions that were occurring was brought into stark relief after the company began installing collision mitigation systems on its tractors. Those systems provided a "tangible benefit" in preventing the front-end collisions. Company officials concluded that if technology could reduce the number of front-end collisions, something could probably be done to improve safety at the other end of the truck.

Gigoux is convinced that the rear-end collisions are the result of either driver distraction or complacency. He says there have been incidents where the car striking the rear of the trailer never even hit the brakes, leaving no skid marks behind.

"We've had fatal collisions where people run into the back us and their cell phone is found lying on the floorboard," he says. "You have a pretty good idea what was going on."

The company debated how to proceed for several months, eventually concluding that the best way to get the other driver's attention would be something out of the ordinary; something that would break the complacency and routine of driving behind a truck.

"We wanted to get people's attention, to make them think, 'Hey, something's happening in front of me that's different,'" he says. "So rather than adding just another brake light to the trailer, we decided to install an amber strobe light fairly high up on the back of the trailer. We hoped that would be enough to make them notice and take action."

Out of the Ordinary

The idea of the flashing amber light came from the advance warning signals that precede some traffic signals at rural intersections. They are used to warn drivers the traffic signal is about to change. 

"We didn't want something that becomes familiar or routine after a while, such as the constantly flashing light you see on some garbage trucks or crude-oil trucks," Gigoux says. "People get used to that after a couple of minutes. We wanted something that, if we're in traffic and we need to slow our vehicle down, tells everybody to get off their phone and pay attention. Something's about to change."

Groendyke began testing various lights on a couple of trailers at its Enid, Oklahoma, terminal in 2014. They wanted the strobe to be visible day and night and during inclement weather, but not too bright as to be blinding. They even tried using aircraft lighting, but found it was too bright. When they settled on the right lamp — an off-the-shelf amber-colored strobe light — they started working on the location on the back of the trailer.

They wanted the strobe to be high enough that a car driving behind a tall pickup truck following the tank trailer could see it.

"Some of our accidents had been not necessarily the person following us hitting us, but the person following that person hitting them and pushing them into our trailer," Gigoux says. "Our trailers are about 11 feet tall. We wanted it high up, but not too close to the rear clearance light cluster. We settled on about nine feet above the ground."

Testing Proved the Theory

Road testing began with a handful of trailers at Enid and later expanded to terminals in Kansas City, Fort Worth and Denver. Drivers pulling the specially equipped trailers almost immediately reported seeing changes in the behavior of people driving behind them. When the brake lights came on (and the strobe began blinking), car drivers began making lane changes sooner to get around the truck, the drivers said. The amber strobe was making people notice that the brake lights were on.  

Groendyke orders trailers with a high-mounted red brake light and replaced it after delivery with an off-the-shelf amber strobe light.  -  Photo: Jim Park

Groendyke orders trailers with a high-mounted red brake light and replaced it after delivery with an off-the-shelf amber strobe light.

Photo: Jim Park

"When we started seeing the good driver feedback, we softly started moving forward with more installations," says Gigoux. "And the next thing you know, we've got almost 900 trailers converted. We were pretty happy when the exemption finally came through, because we did receive quite a few violations for having the amber strobe light tied into the brake light circuit."

Gigoux says the company received somewhere in the neighborhood of 40-50 violations for using the technically illegal additional brake light, but all the tickets were issued in just two states, and one state in particular and one particular scale house.

"They were telling our drivers, 'We know you're putting those things on there and you keep coming through here, so we're just going to keep writing tickets every time you cross our scale,'" he says. "It was really only one or two law enforcement folks at certain scale houses that zeroed in on it. It was unfortunate that those scales happened to be in one of our high-traffic areas."

Tickets or no tickets, Groendyke tracked two groups of trucks for 90 million miles over 30 months. One group was fitted with the strobes, the other without. The data revealed that the flashing amber light that blinked when the drivers applied the brakes reduced rear-end collisions by almost 34%. And it completely eliminated rear-end collisions involving HAZMAT trucks at railroad crossings.

Application for Exemption

In April 2018, after gathering and correlating all the data collected over the course of the trials, Groendyke submitted a formal petition to the Federal Motor Carrier Safety Administration for relief from 49 CFR 393.25(e), the rule that prohibited the use of anything other than a steady burning red light as a brake light. Groendyke was granted the exemption it sought a little more than a year later, on April 26, 2019.

"I think it was just a few days more than a year before it came to fruition, after our general counsel put together all the data from our data analysis group and quoted regulations and presented it to FMCSA in a very formal fashion," says Giroux. "It was interesting that when FMCSA put the exemption out for public comment, they didn't get a single negative comment. And I think it helped that we had full support from National Tank Truck Carriers. We were elated when we finally knew that we would no longer be receiving violations for what we were doing."

NTTC was fully supportive of the application and recently filed for an additional exemption that would allow all tank truck carriers to install similar warning lights. The problem with the regulation in this case is that it limits the use of such lighting to emergency vehicles. While people still drive into emergency vehicles, NTTC president, Daniel Furth, says distracted driving has reached epidemic proportions and carriers need to be able to take some steps to protect themselves, especially in situations where HAZMAT haulers are forced to stop at rural railroad crossings.

Complacency caused by hours of driving can cause the scene ahead to become a mind-numbing blur. A flashing amber light can shake away the haze.  -  Photo: Jim Park

Complacency caused by hours of driving can cause the scene ahead to become a mind-numbing blur. A flashing amber light can shake away the haze.

Photo: Jim Park

"If you have [a distracted driver] approaching from behind, you can see at some point that it's not going to stop. You're like, this guy's gonna hit me," Furth says. "With those trucks having to stop on rural railroad crossings and other spots, it was causing problems.

"In light of our petition, we're hoping that they change the rural railroad crossing rule as well, but that's a whole different issue," Furth adds. "Other drivers forget that HAZMAT trucks must stop for railroad crossings and many of them aren't all that well marked. Back when they came up the rule, it was a great idea. But now, with all the distracted driving, anything that can help reduce collisions has to be seen as worthwhile."

Also supporting NTTC's application is Transportation Safety Equipment Institute, a non-profit trade association serving the needs of manufacturers of OEM and aftermarket motor-vehicle safety devices and associated equipment. TSEI's executive director, Paul Menig told HDT that crash statistics show that about 20% of all collisions are rear-end car-into-truck incidents.

"We have under-ride rules to mitigate injury and the loss of life from those incidents, but there's nothing in the rules that address brake lighting in a way that might help reduce the number of crashes in the first place," he says.

Menig says getting the exemption in place for all tank truck carriers would be a huge step forward. He stresses that the installation of such warning lights will remain voluntary and up to the discretion of the carriers. He also notes that the National Highway Traffic Safety Administration is already looking at Groendyke's results but would have a much larger sample to study if NTTC's exemption petition is granted.

Broader applications beyond tank trailers could be challenging, however. The installation on a tank trailer is fairly straightforward, but not so easy on a van trailer with swinging or roll-up doors, and probably impossible with open-deck trailers. Mounting the light high on the rear of a van would interfere with the clearance light cluster. Mounting the light in the door has obvious drawbacks, and mounting it low, with the other brake lights would likely limit its effectiveness.

On open deck trailer hauling over-size loads, which are in some cases required to use flashing amber warning light, the flashing amber brake light could be confusing and probably of limited utility.

"Those are all issues NHTSA will have to look at before coming to any conclusion on the use of flashing amber stop lights," Menig says. "It will likely be several years before we hear anything concrete from them."

DIY Brake Lights

Groendyke ordered trailers from their suppliers with a standard high-mounted stop lamp, and simply popped out the red lamp and put in an off-the-shelf flashing amber strobe light.

"Our suppliers were not going to build a non-compliant trailer, but high-mounted stop lights have been commonplace in cars since probably the 1980s," says Gigoux. "I see a lot of trucks that have a third brake light back there, and the trailer manufacturers didn't have any issue with that from a compliance standpoint."

Interestingly, the flashing amber stop lamp also works with the engine brake. It's a question that pops up often in conversations about brake lights. Why not have the brake light come up when the engine brake is activated? There's some doubt about whether that's legal or not, but apparently it is. Groendyke discovered that more or less by accident.

"Some of our drivers told us that the strobe was staying on after taking their foot of the brake," Gigoux says. "After some investigation, we discovered that the engine brake was wired into the brake circuit through a programmable engine setting. On some of the new trucks we ordered, the the engine brake/brake light on setting was turned on as a default setting. And you know, that's not a bad thing. If it's your intention to slow down, other drivers need to know that."

Groendyke Transport went a "rogue" on the installation of the amber strobe light, Gogoux told HDT. They determined something had to be done to lower the number of rear-end collision they was experiencing -- some of them fatal. So, company undertook the measure and proved it with data accumulated over more than two years and 90 million miles, all without first seeking permission from FMCSA or NHTSA.

It's worth noting that Groendyke is an eight-time winner of the National Tank Truck Carriers North American Safety Champion Award, known as the Heil Trophy. The company obviously takes safety seriously, and went into this eyes wide open.

In hindsight, we can only wonder if FMCSA would have granted permission for a trial of the amber strobe light if the company had played nice and sought permission first. There have been intensive efforts over the years to address the issue of rear-end collisions, like the underride guard mandate, which has cost the industry millions of dollars. Underride guards are good at what they are designed to do, but they are useful only after a collision has occurred. The blinking amber brake light is designed to (and already has), prevent collisions from happening in the first place.

Good on Brian Gigoux and the rest of the team of professionals at Groendyke for taking the initiative on this. I hope FMCSA wipes from the company's record the violations it incurred while advancing this brilliant safety concept.

About the author
Jim Park

Jim Park

Equipment Editor

A truck driver and owner-operator for 20 years before becoming a trucking journalist, Jim Park maintains his commercial driver’s license and brings a real-world perspective to Test Drives, as well as to features about equipment spec’ing and trends, maintenance and drivers. His On the Spot videos bring a new dimension to his trucking reporting. And he's the primary host of the HDT Talks Trucking videocast/podcast.

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