The next time you’re driving behind a semitrailer take notice of that metal bumper hanging off the back. That’s the underride guard, and its job it to prevent your minuscule hatchback from hurdling beneath its hulking mass on the off chance that you have a collision.
Sadly, not all guards are created equal and some buckle during an accident — allowing the car’s passenger compartment to impact the rear of the trailer, frequently shearing off the part of the vehicle that your head occupies.
To further scare you out of tailgating trucks, the Insurance Institute for Highway Safety released a 2011 report stating that the majority of those guards would fail and that the National Highway Traffic Safety Administration’s minimum structural guidelines for underride bars was inadequate. While some manufacturers had begun installing stronger and safer guards, mainly to satisfy higher Canadian standards, the initial round of IIHS’ testing resulted in most underride guards failing in a 30-percent overlap test.
Since those earlier findings, IIHS recorded a significant annual increase in fatal accidents involving passenger vehicle rear-endings of large trucks through 2015. It has also reached out to the NHTSA to impose more stringent regulations on guard manufacturers.
However, many of those earlier-tested underride makers took matters into their own hands and made changes to guard designs, enhancing the feature’s overall safety before regulators turned it into policy. Impressed, the institute praised the companies for not waiting for mandatory NHTSA guidelines.
“IIHS isn’t a regulatory agency, and other than safety, there was no incentive for semitrailer manufacturers to make improvements,” IIHS executive vice president and chief research officer David Zuby said. “When we started testing, we weren’t sure how they would respond. These companies deserve a lot of recognition for their commitment to addressing the problem of underride crashes.”
The institute now has a new “Toughguard” award to bestow upon those companies producing guards specifically designed to prevent a range of underride-related fatalities — including the often-deadly overlap crash. Many even worked with IIHS, asking for retests, to evaluate how to improve safety.
Great Dane, Manac, Stoughton, Vanguard, and Wabash were the manufacturers issued the new award for making changes that exceeded the current rules in place in both the U.S. and Canada. Their updates also surpassed the proposed NHTSA requirements, which would essentially align U.S. underride regulations with the higher Canadian guidelines.
[Images: Insurance Institute for Highway Safety]
It’s called the “Mansfield bar”, and its genesis goes back to a triple fatality accident involving the actress Jayne Mansfield, on a Louisiana highway in 1967:
https://roadtrippers.com/stories/jayne-mansfield-bar
Pro tip: Don’t image search Jayne Mansfield with the “safe search” off…
Pro tip addendum: But totally do it when you get home.
I’d hit it.
Too soon?
Too late.
Brings back memories of the “READ UNDERRRRIDE CRASH” video from drivers’ ed. You have to read that in a serious narrator deep voice.
At least the way I read this story, the current effort to improve seems to be a collaborative, cooperative one. And that’s a good thing.
And, indirect brush with fame? My mom worked in the same office with Mansfield’s first husband (Paul), many years ago.
The “professional drivers” piloting trucks are why I get the hell away from them as soon as possible.
Not that car drivers are great, but I’ve seen a lot of truck drivers that seem to forget that they’re driving tens of thousands of pounds of death down the road.
You mean that *wasn’t* a professional driver who put on his signal the instant he started moving over, going up a long, steep hill 5 under the limit so he could pass the other truck going 6 under the limit? Color me shocked!
I love the self-righteous “I have blind spots” signs on big rigs operated by drivers who change lanes based on the law of gross tonnage.
It was that window-height bumper which clipped/brushed my minivan’s passenger mirror around 2002, as he passed the truck in front of him without realizing I was already in the passing lane.
I saw his turn signal, thinking he had applied it proactively and would pass after I passed him. Instead, he came right over while I was next to the cab. I hit the brakes as hard as I could at 70 mph, veering for the Jersey barrier, applying full horn and high beams all at once (it was night time). Thankfully, our only contact was a slight brushburn on the mirror housing as his bumper passed by.
I’ve never had a more scary moment in a car.
You still hanging onto that anger over a broken outside mirror for 15 years?
Wow.
My scalp healed fine but I’m still holding on to the anger from being pistol-whipped during a mugging 42 years ago.
Lethal threats will do that to you.
@April S: I’m not angry; I’m merely remembering what it felt like to have 40 tons of truck contact my car at speed on the highway.
We had a tomato truck do that on southbound I-69 in Indiana. He NEVER flinched or anything. Stayed in the left lane for miles… I should have shot his tire out!
JimC2, I take it you never operated a truck tractor and 53′ trailer set before.
Nope. Biggest thing I’ve ever driven was a 22′ Penske towing my car on a trailer. And you know what? When I didn’t have the oomph to keep up with traffic in the fast lane, I didn’t try crap like pulling into it and cutting people off by doing so. But you’re right, I’ve never been a “professional” long haul teamster, so what do I know…
unless you know they are in the union, they are not Teamsters. they are truck drivers.
/pedant
That’s why I used a lowercase t.
/oldfashionedtermfromthe1800s
Ooooo 22 feet, You must be a “pro”.
“Ooooo 22 whole feet, I guess that makes you a “pro”.”
Obvious troll is obvious.
Point being, a little rental truck and trailer is faster than a tractor-semitrailer but I still knew when my vehicle was too slow and didn’t belong in the left lane.
No troll. it is just a little irritating how some people talk crap about having to share the highway with commercial trucks. If you drove one you just might be a little more understanding. It’s not easy.
“law of gross tonnage”
This is a good description of the way most car drivers treat pedestrians, too.
True- and right of way or not, I move my foot over the brake pedal when a pedestrian looks like they might step into the street. Just good sense.
“I love the self-righteous “I have blind sp…”
I assume He Is BLIND!!! and make it a point not to hang out in that area. I don’t give a sh!t who was there 1st or who has the right of way. Something about “self-preservation” overrules.
Like traffic always gives you a choice.
Blind spots have nothing to do with suddenly moving into faster moving traffic ;)
And a LOT of truck drivers do the turtle race thing, that is, “I’m going uphill 5 under the limit so I am going to try to pass the other truck going 6 under the limit.”
It is what it is. But you’d be wise to hang back, then slingshot through his blind spot, once traffic ahead clears. Look out for the trucker’s “needs”, like his lane ending ahead, or him coming up on slower trucks. When you do others a favour, you’re also helping yourself.
When approaching a group of trucks and you have an open lane, rocket past, they may need your lane soon. You lollygag, you lose.
“… slingshot”
Oh trust me, I do just that, and I don’t hang out in the blind spots.
The DOT is constantly tightening the screws on truckers, and everyone else may get delayed a bit more, or worse, but we need to work together with them, not just for safety.
Most cars merge on to the freeways and expect truckers to adjust to THEIR speed, or lack of it, and or move over for them. I see truckers locking up their brakes all the time, from drivers that enter the freeway, not looking over their shoulder, basically with “tunnel vision”.
They can’t blast the air horn at them, they may panic and slow down even more, (and faster than the semi can stop). Then you have two-wide in a single lane!!
The “laws of physics” don’t compute for many drivers.
“… we need to work together with them, not just for safety.
Most cars merge on to the freeways and expect…”
I would love to see a meaningful “highway patrol safety blitz” targeting stupid driver tricks instead of just “speeding.”
– Set up a trap near an entrance and bust people who suck at merging (lackadaisical acceleration, mysteriously tapping their brakes on a perfectly straight onramp, pulling into the travel lane well below traffic speed when there is plenty of acceleration lane remaining). Give them written warnings, doesn’t have to be heavy fines as much as I would love to see that out of spite.
– Also bust left lane slowpokes. This has improved a lot in just the last few years… do it more!
– Bust trucks holding up traffic on long grades while they do the turtle race up the hill.
Sheesh!
Americans suck at merging. It’s never taught, and hardly ever learned. That’s why “cloverleaf interchanges” failed miserably. Now we have to have the tri-level flyovers.
The image of truckers is most are dumb and dumber, that’s why they’re otherwise unemployable. That’s hardly ever the case. Guaranteed 99.99% take pride in what they do and their professionalism. They’re the absolute last ones to get into a road-rage situation.
Get to know some truckers starting here:
youtube.com/watch?v=NYdkOO_oulo
DenverMike. So true. It’s a tough job. Those who complain that tractor trailers are being slow pokes on purpose is nonsense. Most engines these days are equipped with governors plus the need to keep engine rpms at a certain range. It’s not easy when you have a loaded trailer going up a grade. Plus those things are not hot rods.
Listening to Mistress on how things went during her training gave me a different perspective. That we four wheelers really need to give them a break.
Ask any long-haul trucker. They prefer driving all night. No cars to deal with. Except most folks don’t know any truckers, none, just the stereotypes.
Truckers are mostly loners and always on the road. They’re almost never home, if they even have a “home”.
For truckers, speed governors/limits, log books, weigh/inspection stations, deadlines, etc, make every mile and minute *count*.
Everyone wants their favorite products on the shelf/rack/case, and cheap, but know little, or care what it takes to get them there. Do they think the just magically appear?
Its about time! As someone who drives a sports car every day these things scare the crap out of me. Those bars are clearly not a crush zone and at the worst possible height. I know… I should join the rest of my fellow lemming commuters and just get an SUV or truck to be “safe”.
“my fellow lemming commuters”
Nothing wrong with being a lemming if you’re smart enough to stay in the flatlands.
The whole “lemmings run off cliffs” bull$hit was compeletely and literally staged by Disney for the 1958 “documentary” White Wilderness.
“These bar test results don’t matter, until the IIHS can tell us exactly which cars run into the back of the bars, and the age of their drivers. Til then, don’t matter.”
not only are these 18 wheeler dangerous, so are the tire remnants they leave behind when they blow up, forcing others to sharply change lanes at high speeds to avoid hitting them. It has happened to me a couple of times and it was not pleasant.
I’m sure they are doing it on propose.
They’re not, but it’s dangerous.
I respect truck drivers a lot. In many years doing a fair amount of highway driving (midwest/upstate NY) it’s other cars I worry about, not trucks. There are two exceptions. Truck drivers can get sleepy and start wallowing and losing lane discipline. The second is the tread they leave behind. I have lost a tire and the plastic underneath the engine in two separate occasions. Nothing scary like SCE reported above yet for me…
Those bars are too flimsy and too small. They could certainly be improved at little cost, considering how important their function is.
I saw one bar that was dramatically improved very cheaply. Someone wrote the hand-lettered message, “TEST YOUR AIRBAGS HERE”.
they have a little known second function as well-
when backed into a loading dock, “dock locks” hook the back of the bar so the trailer cant be moved when loading and unloading. forklifts are heavy and have enough momentum to move trailers.
@SoCalMikester…Oh ! You beat me to it. Rules for a 53 footer
1…The trucker needs to unlock his Tandems , apply his trailer brakes and slide the tandems to the back of the Trailer. Not the most pleasant job at -15 F
2…Driver must open his barn doors, and back into the dock, and chock both sides of his tandems.
3…Dock tech {that was me} and the lift truck driver ensure that the IIHS bar is locked by a spring mechanism, and the load ramp is activated.
4 The dock tech , or the lift truck driver, check for the chocks, and the tandem slide. {the upside of this little duty ? } GM buys the Lift Truck man, and the Dock Tech a winter Parka.
5 ..All personal including management must wear a reflective vest while in the Dock Area.
Any employee and or truck company employee in violation of these rules will be subject to discipline , up to and including dismissal.
I spent 12 years as a shipper receiver / dock tech. We operated under the guide lines of “Just In Time’…I personally dealt with 1000’s of truck drivers..Like any group, from any occupation…Yes, we had a few a$$….wholes …..For the most part they were just guys, and a few girls, that wanted to get their job done, safely and get back on the highway.
Wow. I worked in a large-scale independent cookie factory in the late ’60s while in college ($3 million annual sales, big money back then for a regional bakery). Truckers were given two rules: ignore the garbage man – he’ll get out of your way; and watch out for the owner in a blue Pontiac LeMans on your way out – he never looks when he backs into the yard exit lane. The rules as far as backing up to the makeshift dock on an 1854 textile mill: just line up with the door opening.
I’ve always wondered…
Why are semis in the USA so high off the ground vs those in Europe? Is there something historical here?
I’m guessing dropping ride height at this point would be monumental since loading docks etc are already built at a particular height?
Not all 40-footers are high. A moving van has a low middle section for ease of unloading furniture and the like. Most semis are just flatbed trucks with a box, the flatbed strong enough to handle heavy cargo and even drive a forklift from a dock onto the truck.
American semis are also built to travel longer distances on wider roads than European ones, with more consistent laws and regulations. The EU zone isn’t that big, and traveling American distances in Europe will get you into different countries with a whole mess of different standards, as well as languages and currencies/taxes.
i read somewhere that some companies are moving to “box in” the section of “mansfield bars” so they provide security along the sides as well. bars in the back are great, but if someone blows a stoplight and t-bones a trailer, then its not so great.
Considering how slowly semis are able to brake, it takes a lot of work to rear-end one of them, especially with enough violence to do something like what is pictured here. Having spent 10 months driving all cross-country and all around the American west pulling a 28′ travel trailer, I have some appreciation for the difficulty the drivers of these vehicles have (my “rig” was about 49′ long, end-to-end), although with 420 hp at my disposal, I had a much more favorable power-to-weight ratio than they do. The worst behavior that I have observed by long-haul truckers is staying about 15 feet off a car’s bumper, while exceeding the speed limit on a downgrade. I get what they’re trying to do — build momentum for the coming upgrade — but if the car in front has a blow out, the result isn’t going to be pretty. Pulling my trailer, with a self-imposed speed limit of 60 (dictated by the 65 mph limit on my trailer tires), I tried to avoid the Interstates, except in California, which has a posted limit of 55 for all towed vehicles, including semis.
The great majority of problems I observed were created by the “4-wheelers”) who just didn’t appear to be thinking too much. For example, a semi (or me) trying to merge on an on-ramp needs both more space to fit in and accelerates at a fairly slow pace. Countless times, a car in the right lane doesn’t move over to the left lane to accommodate me (or the semi), even though it is free.
A very long time ago, when I had to get a California driver’s license (because I was working there for a summer), one of the unusual things I learned is that merging traffic had the right-of-way over traffic on the freeway . . . and this seemed to be observed pretty religiously. I have now idea what the law is now, but whatever it is, the practice of allowing merging traffic to have the right-of-way in California seems pretty much dead.
As far as dealing with trucks go, life is better if you understand their imperatives and accommodate them: (1) they’re much longer than you, (2) they accelerate and stop in much greater distances than you, (3) they often have speed governors on their tractors, (4) they can’t see directly behind their trailer and (5) they’re on a schedule.
My experience was that in the great majority of times when they wanted to pass me doing 60, they appreciated a lights flash from me when the rear of their trailer had cleared the front of my truck and they signaled for a change back to the right lane, especially when they had a train of cars behind them.
A “Zen” approach to driving (fitting in with the other drivers by understanding and accommodating their needs) will usually get you there faster and more safely… and with less personal stress.