[Rehaan]

What Is An Under-Run Bar?

See that horizontal bar mounted behind the rear wheels of the trailer? That's the Under-run Protection Bar:


Here's what it looks like on an Indian truck:



How Does It Work?

Accidents are designed to be bumper-to-bumper contact. This is because modern cars are constructed to keep the passenger compartment intact, whilst allowing the front and rear crumple zones to absorb the majority of the impact.


source

Trucks have large overhangs and no bumper:


As a result, in the case of a collision, the smaller and lower vehicle tends to "ride under" the truck's long overhang:


The A-pillars of a car are not designed to absorb or resist impacts. As a result, the passenger compartment takes the full brunt of the impact. This causes severe head and upper body injuries to the passengers. These type of accidents have an extremely high fatality rate. Watch this dummy get hit in the face by a truck. OUCH!



You can see how the rear end of a truck has deformed the A-pillars (ie. the vertical pillars on either side of the windshield):


Everything above hood-level has been impacted, but the crumple zones and bumper haven't had a chance to do their job as they didn't make contact with anything:


That's where the Under-run protection bar comes in. Think of it as a bumper for trucks:

source

The Under-run protection bar enables small and large vehicles to make bumper-to-bumper contact. This greatly reduces fatalities & serious injuries to the occupants in the car.

Note the difference between the two here:



Theres another problem too. Side impacts:

source

This was seen in the recent Palm Beach Road accident, where a Ford Figo hits (and runs under) the side of a truck at a junction:

http://www.youtube.com/watch?v=Ak69pwTTofI

But theres a solution for side impacts as well - Side Under-run Protection :

[Rehaan]

What are the shortcomings?

PROBLEM 1: Under-ride bars are mounted too high, leading to the wedge effect.

Well, I guess this kind of demonstrates it:


...but, this is probably a more relevant illustration:

Source

So to prevent the wedge effect, the under-run bars need to be mounted at a typical car-bumper height:

"Rear underride guards must be placed at a maximum height of 400 mm from the ground on an unloaded truck in order to be effective in avoiding underride of light passenger vehicles." - Source

If this maximum height is not adhered to, the rear guard becomes virtually useless.

PROBLEM 2: A lot of under-ride bars are not constructed well enough.

This causes them to collapse when they are hit hard, or just on one side. This results in the car traveling under the truck. In the USA, even though under-run protection is required by law, the laws aren't strict enough. A recent study of several trucks showed that only 1 of them did satisfactorily well on an off-set collision test.

Keep in mind these test were run at 35 mph (only 56 km/h):

http://www.youtube.com/watch?v=C3MPKLy9qHU

Scary crash. If the under-ride bar was ideally constructed, the car's windshield wouldn't have even touched the truck:

source

Even a difference of a few inches in the construction can lead to a much weaker under-ride bar. In this example the placement of the car, the car's speed, and the bar's length & material are all the same in both. But, spot the difference in crash results:

(Hint: The under-ride bar on the right has the vertical members much closer to the center of the truck. They should be further out.)

PROBLEM 3: Under-ride protection isn't present on all trucks in India.

If you rear-end a truck, even at a fairly slow speed, the lack of under-ride protection could mean extremely serious injury to your upper body and head, regardless of how safe your car is.

In just 8 Indian states, recklessly parked trucks have caused the death of 8,304 people in 2 years (2009-2011)! Link

The ARAI website says: "Under run protection devices such as Rear under Run Protection Device (RUPD) and Lateral under Run Protection Device (LPD) are mandatory on heavy vehicles as per IS 14812 and IS 14682 respectively."

I've been told that as per the rules, all three types (Front / Side & Rear Under-run protecting devices) are now being provided on trucks (ICV and above).

However, even though these regulations are in place, the shortest of highway trips will show you that there's still a long way to go before all trucks are suitably equipped with under-run protection.

Case in point:


Another guillotine-on-wheels. Not a single tail-light in sight:

[Rehaan]

Keeping Yourself Safe:

• Golden Rule: Try your best to avoid following trucks on the highway (especially ones without under-ride bars!).

• There's plenty of other good reasons not to follow trucks too: they obstruct your visibility of the road ahead, they throw up dirt onto your windshield and kick up stones as well. A lot of trucks don't have well maintained brake lights or a high-mounted 3rd brake light either.

• Remember the 2-second rule when following any vehicles. Keep a very safe distance.

• Avoid driving at night (abandoned trucks with no rear lighting, slow-moving trucks with dirt-covered lights, etc).

• Avoid driving in poor visibility conditions.

• Read more tips on highway driving here.

The next time you're out on the highway, make a note of how many trucks are devoid of under-run protection, then remember this thread and drive safe!


Thanks to various BHPians for some of the pictures.

[SmartCat]

1) The buses we see on our highways are dangerous too. The body is mounted on a very high chassis. Volvo buses are OK in this aspect, but they have rear mounted engines. I wonder how safe that is!

2) To be on the safer side, ask the passenger sitting next to you to watch out for trucks (And pedestrians. And cyclists. And cows) parked on the road while driving in the night. Especially, on a two-laned highway where you can be affected by high beam of the oncoming traffic.

3) Big SUVs are safer than cars, in these circumstances. But, on the flip side, most SUVs are prone of rollovers and don't take to quick lane changes very well. A good compromise would be crossovers like Honda CRV - high bonnet and car-like dynamics.

[DRIV3R]

An informative read, thanks for sharing Rehaan.

I feel that the below case is a good case for the topic in hand. The car was sandwiched between two trucks, and was protected by the under-run bar of the truck in front. (You can see that it is bent after impact)

http://www.team-bhp.com/forum/street...ml#post2876743

[mpksuhas]

I remember around ten years back (~2003 or so) under-run bars made a sudden appearance in many trucks. Initially many people were not sure what was the purpose of the same.
However like many laws I feel enforcement of the same has taken a back seat after the initial period.
Also, does anyone know if the bars are factory fitted in new vehicles ?

[Mohan Mathew A]

I have always wondered if this is required under law why is that manufacturer's don't always provide it.

The sad thing is that even the safest sedan's will be of no use as they probably will be the worst affected as they are low slung

[Rehaan]

Originally Posted by DRIV3R

I feel that the below case is a good case for the topic in hand. The car was sandwiched between two trucks, and was protected by the under-run bar of the truck in front. (You can see that it is bent after impact)

Nice find!

I'm no expert, but it does look to me like that under-run bar was a bit high - since the Punto has submarined + the Punto bumper doesn't seem damaged + the bonnet has been scraped up.

If i had to guess, i'd say the presence of that under-run bar (regardless of how poorly/well it was constructed) definitely helped, but overall it mustn't have been a very fast impact.

Originally Posted by mpksuhas

Also, does anyone know if the bars are factory fitted in new vehicles ?

I've been told that as per the rules, all three types (Front / Side & Rear Under-run protecting devices) are now being provided on trucks (ICV and above).

^ Not sure if all manufacturers follow this, or what the enforcement of this is like. Will let some of the Commercial Vehicle experts answer this one!

cya
R

[the_skyliner]

Fantastic article! Thanks for putting it up, Rehaan!

After reading this article, I am forced to rethink about by decision to buy a sedan. I think cross-over makes lot of sense in terms of safety on our roads. For example, X1 will be more safe than 3 in this particular case.

Such a simple thing like Under-run bars can save so many lives but yet no one cares, neither the truck owners/drivers nor the authorities.

Under-run bars have opposition from truck drivers because sometimes it creates GC issues, especially in case of tippers which carry sand/coal/etc and have to travel to river beds or rock/coal mines. Here a fold-able under-run bar could be a solution.

For regular truck drivers, they see it as an additional cost to save someone else life. Manufacturers should put these bars right at factory then. That could help somewhat.

I have spoken to few truck drivers in past to understand what they know about safety and it is not surprising that they know nothing. So how can we expect them to care if they don't even know the logic behind.

Authorities like RTO should take up education of drivers and especially truck drivers seriously so as to at least create awareness if nothing else. Educating drivers is a must if we want to make our country roads a safer place.

I would suggest that we BHPians should start contributing by spreading awareness regarding such simple safety measures to make a difference. I am game for it and have already started thinking about the way forward.

[phamilyman]

I think this article is not enough. Its well written but what we really need is for BHPians living near major companies, to click photos of trucks going there, and name/shame the company involved.

e.g Maruti's gurgaon plant produces well over a thousand cars daily. That's atleast 150-200 trucks of cars going out, along with an equal number of trucks ferrying in raw material.

Now if we can create a thread with 20+ photos of trucks that essentially are involved with Maruti, but do not have these safety bars, then essentially Maruti is helping put trucks on road that may tomorrow kill the very customers that keep Maruti in business. No ETHICAL company would support this kind of safety non-compliance.

Only a forum like TeamBHP can exert the public pressure on companies such as auto mfrs (for starters) and truly be an agent for good.

Here are two trucks waiting outside the "Atlas Chowk" entry in Nov 2011. I did speak to the driver of the Krishna company truck but he was clueless. Just look at the overhang of these vehicles!


Maruti, are you listening? I know among the Indian manufacturers your esteemed organization has excellent standards all around - but you may wish to drill some sense into your suppliers as well.

[Rehaan]

Originally Posted by the_skyliner

Under-run bars have opposition from truck drivers because sometimes it creates GC issues, especially in case of tippers ... ... Here a fold-able under-run bar could be a solution.

Yes. Systems like this exist. Read more here.


And here...

Originally Posted by the_skyliner

I would suggest that we BHPians should start contributing by spreading awareness regarding such simple safety measures to make a difference.

That is my goal here. Awareness.

First, people need to be aware that there is a problem, and then know that there is an existing simple solution.

After that, for the next steps, I'm not sure. Hopefully we will have a better idea once people chip in regarding what the current regulations are, are they retro-active, are the truck manufacturers responsible or the owners?

Originally Posted by phamilyman

I think this article is not enough.

Agreed. My thoughts on it are above.

Thanks for the pic. I spent hours searching for exactly these long-overhang vehicle carrier pics on TBHP but couldn't find any!

cya
R

[the_skyliner]

Originally Posted by Rehaan

That is my goal here. Awareness.

First, people need to be aware that there is a problem, and then know that there is an existing simple solution.

After that, for the next steps, I'm not sure. Hopefully we will have a better idea once people chip in regarding what the current regulations are, are they retro-active, are the truck manufacturers responsible or the owners?

Yes, I agree and this article will help people as well as manufacturers to be aware of the risks related to accidents involving trucks.

My concern was more towards the truck drivers as there lies the root cause of this problem. Manufacturers may provide under-run bars on the new trucks but there will still be lot of already sold trucks plying on our roads without it.
Also, while "building" the truck body truck owners/drivers might remove them if not properly educated regarding the risks behind doing it.

I was more pointing towards direct interaction with the truck drivers to spread awareness. I used to do it in past whenever I got opportunity on "dhabas" or fuel stations. Nowadays, due to family I don't stop on "dhabas" anymore.

[Gannu_1]

Nicely compiled Rehaan! Thank you for the compilation.

Speaking of long overhanging loads of vehicles, during my return trip from Bombay last time I came across a trailer on the 4-lane NH carrying a reactor column which resembled something like this albeit a bit smaller:



(Image for reference from Google)

The column was protruding outside the trailer for at least 3-4m! The worst part was the absence of reflectors or makeshift lights which are usually attached to the overhangs notifying the trailing vehicles. Unfortunately we couldn't click a snap since we overtook the vehicle quickly. Extremely dangerous especially during the night!

[W.A.G.7]

Nice informative article. Are these under run bars provided by the manufacturer itself, when the truck rolls out of the assembly line? Or are these welded later on by the truck owners to comply with the RTO guidelines?

[itwasntme]

I have observed that only the OEM/authorised builder-built body + chassis have the proper quality of steel and proper mounting of such under-run bars.

Usually they entire 'attachment' is an after-thought with simple weld-ons and substandard steel which will simply collapse or cause submarining during a high-speed impact. They are only for show.