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Old 16th December 2013, 14:47   #16
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

The under bars sure provide protection to modern cars with crumple zones. yet they still do not absorb any impact by themselves and still is like hitting against a dead obstacle. The ground clearance except for the axles are way too high for Indian trucks or buses.

These things should be strictly enforced with some specification provided to the manufacturers. In my last week's highway trip 95% of the trucks had not tail lamps which is even more of a issue in the night. Only saving grace was the reflectors which made them better than bullock carts.
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Old 16th December 2013, 15:14   #17
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

Thanks Rehaan. I've seen them, but never knew they were called 'Under-Run Bars', and though I had an idea of how they'd work/help, I feel a lot more informed after having read this thread.

As someone who enjoys road-trips, this is a very useful and informative read. Thank for sharing.
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Old 16th December 2013, 16:04   #18
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

While the under-run bars do help save lives in an accident but it is also problematic at times. Recently a colleague had the bumper pulled off on his new amaze by the under-run bar of an idiotic truck driver who wasnt even bothered to look around. My colleague had no place to move around to avoid it because there were vehicles behind and to the side while this guy was moving diagonally in front and ended up having his front bumper ripped off by the end of the under-run bar
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Old 16th December 2013, 16:17   #19
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

Quote:
Originally Posted by srishiva View Post
The under bars sure provide protection to modern cars with crumple zones. yet they still do not absorb any impact by themselves and still is like hitting against a dead obstacle. The ground clearance except for the axles are way too high for Indian trucks or buses.

These things should be strictly enforced with some specification provided to the manufacturers. In my last week's highway trip 95% of the trucks had not tail lamps which is even more of a issue in the night. Only saving grace was the reflectors which made them better than bullock carts.
On a recent highway trip, part of the journey was during night time. Couldn't notice any truck with the under bars & as you pointed out the tail lights were either not working or covered with dirt, making them almost invisible.

Though newer trucks do feature the under bars they aren't widely implemented I believe. At times I have seen the under bar is actually placed at a greater height than required.

Once, was able to talk to a truck driver & asked him why the under bar (as per him it is a "rear rod") is placed higher than normal. He replied "saab, road pey bahut ghade aur speed breaker hote hai, kafi baar rod lag jati hai, isliye height thoda zyaada kar diya" (There are many potholes & speed breakers on the roads, many times the rod grazes the rod, hence have increased the height) . I was shell shocked at the ignorance.

I mean, safety has taken a back seat & people are more concerned about the bumpers & under bars grazing the roads. Frankly, i haven't noticed a single truck with an under bar grazing a speed breaker.
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Old 16th December 2013, 16:39   #20
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

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Originally Posted by centaur View Post
While the under-run bars do help save lives in an accident but it is also problematic at times. Recently a colleague had the bumper pulled off on his new amaze by the under-run bar of an idiotic truck driver who wasnt even bothered to look around. My colleague had no place to move around to avoid it because there were vehicles behind and to the side while this guy was moving diagonally in front and ended up having his front bumper ripped off by the end of the under-run bar
More than under-runs being problematic, your colleague was driving very close to the truck. Always keep distance & every Indian truck has that message painted
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Old 16th December 2013, 16:52   #21
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

No he wasnt driving close. Infact he had left considerable distance and halted allowing this guy to move on. But this guy reversed and then diagonally moved ahead which ripped off the bumper. My colleague could not reverse further since there were cars lined up behind him and he could not move to the right either because of the divider. Not at all his fault. When this happened people came and started blaming the truck driver
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Old 16th December 2013, 17:22   #22
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

Good article and it has come out very well with good illustrations.
Additionally there is something called FUPD - Front Under run Protecting Device. This is mandated by CMVR through AIS 069. In simple terms they are fitted below the front bumpers and should be in a height not more than 500mm from ground.

Under-Run Bars on Trucks : Why they are important for YOU!-20130530_121920.jpg

Quote:
Originally Posted by the_skyliner View Post
...
Under-run bars have opposition from truck drivers because sometimes it creates Ground Clearance (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.
Quote:
Originally Posted by Rehaan View Post
Yes. Systems like this exist. Read more here.
Attachment 1179236

And here...
Attachment 1179237
They don't have any GC issues, as in many cases the diff case will be lower most. The problem with them is, reduced angle of departure. Also they are mandated only for on road vehicles. Off road vehicles like tippers, dumpers are excluded. But now for Tippers also, they are specifically asked to qualify it as a surface and mining.

Quote:
Originally Posted by the_skyliner View Post
...
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......
Quote:
Originally Posted by W.A.G.7 View Post
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?
Quote:
Originally Posted by Rehaan View Post
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!
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Originally Posted by Rehaan View Post
...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?...
These are mandated by Central Motor Vehicles Rules (CMVR) and Front, Side & Read (FUPD, SUPD & RUPD) are fitted in the factory. No truck can pass CMVR regulations / sold without them. What's happening is, when they are hit and broken they are not replaced. RUPD gets hit most of the time and they are not replaced/rather insisted by officials. Officials should take strict actions when they find trucks without them.

Quote:
Originally Posted by Rehaan View Post
...
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.
Quote:
Originally Posted by Rehaan View Post
PROBLEM 1: Under-ride bars are mounted too high, leading to the wedge effect.
..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.
CMVR says, we can have upto 60% of Wheelbase (WB) as Rear Over-Hang (ROH). So unlike passenger cars, trucks have larger ROH and hence is the lower departure angle. And again there is min departure angle which needs to be complied. So RUPD's are placed in the exact location which will barely meet the requirements. That doesn't mean that they are just fitted, but are actually collision tested and certified. Also to make things worse, angle of departure is measured for a laden truck and RUPD is for an unladen truck.

Quote:
Originally Posted by Rehaan View Post
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):
Basically RUPD's are kind of crumble bars and are designed to absorb the collision rather than resist it like FUPD. That's the reason, RUPD's looks flimsy with just a round bar as against FUPD which looks very robust. Also FUPD's tends to last longer than RUPD's and will survive minor collisions / accidents.

Quote:
Originally Posted by Rehaan View Post
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.
That's because there is no clause that older trucks needs to have this. So there are chances that they were produced and sold without RUPD and continue to run.

Last edited by Rehaan : 17th December 2013 at 11:03. Reason: Expanding "WB" and "ROH" to full forms so everyone can figure out what you're saying. Thanks for the info!
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Old 16th December 2013, 17:45   #23
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

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Originally Posted by Rehaan View Post
Under-ride bars are mounted too high, leading to the wedge effect
I completely agree with this. The under run bars are still fairly high. Just to check this I parked my Mondeo behind a truck with an under run bar and I found that my car would easily slip under it and reach the rear wheels. I feel they should be a tad bit lower than they are at present.

Last edited by vikram_d : 16th December 2013 at 17:47.
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Old 16th December 2013, 17:48   #24
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

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Originally Posted by Ashley2 View Post

They don't have any GC issues, as in many cases the diff case will be lower most. The problem with them is, reduced angle of departure.
Agree with you, in fact reduced angle of departure is what was in my mind too.

Quote:
Originally Posted by Ashley2 View Post
Also they are mandated only for on road vehicles. Off road vehicles like tippers, dumpers are excluded. But now for Tippers also, they are specifically asked to qualify it as a surface and mining.
Tippers and dumpers should not be excluded from the rule as they also use normal roads. Agreed that they are half of the time off road but then rest of the time they are equally dangerous without the under-run bars. And they are on roads at night as well.
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Old 16th December 2013, 20:29   #25
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

Thank you Rehaan for posting this.
A very very informative article. And yes, like many others have said, the need of the hour is Awareness. I have posted this T-Bhp page on my facebook wall. May I suggest that we ALL post the link on our social media sites.

Thank you.
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Old 16th December 2013, 22:01   #26
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

Thank you Rehaan for very helpful post !

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Originally Posted by Rehaan View Post

See that horizontal bar mounted behind the rear wheels of the trailer? That's the Under-run Protection Bar:
Just curious - I see that most of these Bars are made of MS - look more resisting the crash than absorbing the crash energy. What is the best material to fabricate the Under-run Protection Bars?
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Old 16th December 2013, 22:35   #27
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

I believe that Trucks ought to be stopped when entering a new state, and checked for height of under-run bars, working lights etc. I would rather cops were used up in doing that than stopping people who don't wear their seatbelt or a helmet (though, I advocate it, it is like having more people out there to stop suicides rather than murder)
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Old 16th December 2013, 22:40   #28
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

Equally important is the side under-ride prevention bars.
Many European nations adopted side under-ride guards, beginning in the mid-1980's, and they were originally intended to stop bicyclists, motorcyclists, and pedestrians from becoming entrapped under the sides of trucks. Yet, such side guards have proven to also work well to stop cars from continuing beneath the sides of the large trucks and trailers.
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Old 16th December 2013, 22:45   #29
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Post Re: Under-Run Bars on Trucks : Why they are important for YOU!

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Originally Posted by the_skyliner View Post

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.
Thanks for this very informative article. I think every driver who enjoys road trips/ drives frequently at night, and especially the truck drivers themselves should be made aware of this ! Though I'm pretty sure the article will be read by all of us here and will spread through word of mouth, but as the_skyliner mentioned here, the RTO or another authority must take up the initiative to inform the truck drivers. Otherwise, if Team BHP ourselves could somehow take up the initiative..
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Old 17th December 2013, 01:10   #30
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Default Re: Under-Run Bars on Trucks : Why they are important for YOU!

The under Run bars are mandatory for all OEM truck manufacturers under the CMVR norm under section - (forgot the number)
But the sad part is that the body manufacturers remove them, or once damaged they are not refitted back.

The deteriorating law and order in our country doesnt enforce anything on these killer machines.
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