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Old 3rd May 2013, 15:07   #61
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Default Re: Understanding Seat Belts : Layman Language

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Originally Posted by tbppjpr View Post
2. How effective the load limiter actually is?
You can't really test the load limiter, as its usually a one-time use thing. Most of the times its a metal piece that bends when severe load is applied on the belt (the kind of load that is only experienced during a crash).

Read this as well:
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Originally Posted by Rehaan View Post
Seat belts are slightly stretchable.
Yes. You read that correctly. The belt material is designed to stretch ever so slightly under extreme force. The advantage of this is, it further increases the occupant's stopping distance, thereby reducing the deceleration force they experience. Think about it, the difference between punching a cement wall and punching a wooden door is a tiny bit of flex. Other seat belt systems have "load limiters" which let out some extra belt when an immense force pulls on them. Load limiters can even be a fold stitched into the seat belt, which breaks the stitching and unravels more of the belt when it crosses a threshold force. Seat belts also help spread the force over a much wider area across the occupant's comparatively rugged rib-cage and pelvis, rather than a more concentrated & damaging impact to vulnerable areas of the body.

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Originally Posted by tbppjpr View Post
...because the pretensioner is supposed to lock the belt and it will unlock if it detects some release when you move back.
+
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Originally Posted by tbppjpr View Post
... it will get locked at the pretensioner end and won't come out
I think you might be using the word "pretensioner" sometimes when you actually mean to refer to the inertia based locking mechanism that all seat-belts have.

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Originally Posted by CrAzY dRiVeR View Post
In this regard- VAG group cars (Vento for one) had become notorious with the belts getting activated even in the event of fires, and people are trapped to their deaths. Have read atleast 2 such reports in team Bhp too.
CrAzY dRiVeR - this sounds rather misleading and incorrect.

A) You might have read some half-baked speculation in those threads...
B) Even if the belts are pre-tensioned and LOCKED in place (unlikely), its still extremely easy for the person to unclip the latch and remove the seat-belt just like he normally would. Even with full load on the seat belt, a single finger button press releases the clip. I just tried it to confirm too.

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Originally Posted by nkrishnap View Post
On the funny side apart, why would a car's seat belt lock up in the event of fire? Are the sensors getting damaged in fire a cause for this?
It's highly unlikely that seat belts would lock up in the case of a fire. The locking mechanism is located in the B-Pillar, and being mechanical it would take a lot of heat to damage it - by which time the driver would be toast if he was still around. Also, even if the seatbelt did 'lock', I'm fairly sure you'd still be able to release clip/latch.

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Originally Posted by tbppjpr View Post
..do the Linea's pretensioner has any connection with brakes...
Those would be the electric motor or solenoid operated pre-tensioners (eg. Mercedes E-Class "Pre-safe") which can operate more than just once. Nonetheless, they are probably linked to an accelerometer / air-bag sensor (rather than directly to the brakes).

cya
R

Last edited by Rehaan : 3rd May 2013 at 15:11.
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Old 3rd May 2013, 15:49   #62
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Default Re: Understanding Seat Belts : Layman Language

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Originally Posted by DerAlte View Post
LOL That is NOT the pretensioner - that is only the floating seatbelt 'lock' working.
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Originally Posted by Rehaan View Post
I think you might be using the word "pretensioner" sometimes when you actually mean to refer to the inertia based locking mechanism that all seat-belts have.
Thanks for clearing that, exactly that is what I meant and I think that may have created some confusion in the past discussion.


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Originally Posted by Rehaan View Post
It's highly unlikely that seat belts would lock up in the case of a fire. The locking mechanism is located in the B-Pillar, and being mechanical it would take a lot of heat to damage it - by which time the driver would be toast if he was still around. Also, even if the seatbelt did 'lock', I'm fairly sure you'd still be able to release clip/latch.
Actually there is possibility of getting stuck in the seatbelt in case of such panic situation.

When that Vento fire incident happened and person died, two things came in my mind - one was the door locks, which don't get locked from inside in many cars (and Vento is one of them) unless there is any aftermarket security/locking system installed which enables locking from inside. Another thing which came in my mind was that - is there any possibility that occupant can get stuck in the seatbelt even if its working fine?

So I tried experimenting in my car's normal 3 point seatbelt with normal pretensioner. I went in my car, squeezed my body/belly as much as I could and fastened seatbelt. Now I pulled the belt/reel with full force while maintaining same squeezed position of my body, to take the belt out so that it gets locked and it got locked/jammed (the temporary lock, not the permanent pretensioner lock).

Now I released my breath to bring back my body/tummy into normal position, and moved my body frontwards so that the belt/reel remains locked/jammed in position and no space is left for any movement (like how we try to get out of the seat). Now when I tried pushing the belt clip/latch inside the lock but it it didn't have much space to go inside enough so that I can unlock it.

The same thing can happen in panic when person tries to get out of the car and keep pulling himself outside but can get stuck if doesn't open the seatbelt in normal way which we do daily.

This is the situation when presence of mind is highly needed and its expected that the person makes some space between his body and the belt reel so that reel can move-back inside the pillar and gets unlocked and again starts acting normally. Now he can gradually pull it out enough to unlock the latch. If person is stuck very tight in the belt then its the seat, which can always be pushed back fully to make space between body and the belt reel. But again, presence of mind.

This was an experiment, but the same thing has happened with me few more times when I tried getting out of the car in hurry but forgot to unfasten the seatbelt and got stuck in the belt.

Quote:
You can't really test the load limiter, as its usually a one-time use thing. Most of the times its a metal piece that bends when severe load is applied on the belt (the kind of load that is only experienced during a crash).
Now as you said, the load limiter it one time funtion, it can't come handy in such panic situations.

Last edited by tbppjpr : 3rd May 2013 at 15:56.
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Old 3rd May 2013, 16:21   #63
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Default Re: Understanding Seat Belts : Layman Language

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Originally Posted by tbppjpr View Post
... Actually there is possibility of getting stuck in the seatbelt in case of such panic situation.
... is there any possibility that occupant can get stuck in the seatbelt even if its working fine? ...
The situation is never one of 'panic' - it is the person who brings it on. And never forget Murphy's law (as applicable to the human mind).

Yes, it is possible - BUT DUE TO THE PERSON, NOT DUE TO THE FUNCTIONALITY OF THE SEATBELT. If one does a contortion act while getting into the seatbelt, or panics and forgets where the clasp release is - the person will be 'stuck' for their own mistake.

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Originally Posted by tbppjpr View Post
... So I tried experimenting in my car's normal 3 point seatbelt with normal pretensioner ...
Please stop conducting simplistic experimentation that doesn't prove anything to anyone. You will only be deluding yourself that you can replicate something that has taken years of safety research. Paranoia is the subject of medical studies, and not related with seatbelt design.

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Originally Posted by tbppjpr View Post
... Now as you said, the load limiter it one time funtion, it can't come handy in such panic situations.
It is simpler to do yoga and mind exercises to improve 'panic situation' reactions - this is highly personality dependent, not technology dependent.

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Originally Posted by Rehaan View Post
... It's highly unlikely that seat belts would lock up in the case of a fire. ...
Correct - it won't, and never due to fire (that system is fire retardant). Lock up it will, in the case of an accident - it is MEANT to do that. Doesn't mean the snap-latch becomes inoperable - it is unaffected. If the fire is hot enough to overcome that, it doesn't matter whether the driver had presence of mind or not.

In any case, in a modern car, it is possible to drop the seat all the way back and crawl out of the seatbelt. A 'panicky' person won't remember that anyhow - nor any other 'trick' of getting out. It is better that they minimize or stay away from driving altogether.
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Old 3rd May 2013, 17:03   #64
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Default Re: Understanding Seat Belts : Layman Language

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Please stop conducting simplistic experimentation that doesn't prove anything to anyone.
Saar, it looks simplistic to us who spend most of our time here. But I have met many people who express the surprise on how can seatbelt hold occupants in one place when they are so flexible, I myself have explained the seatbelt functionality to many of such co-passengers with that forceful pull and lock. And that number is not very less by any mean.
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Old 3rd May 2013, 17:19   #65
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Default Re: Understanding Seat Belts : Layman Language

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... many people who express the surprise on how can seatbelt hold occupants in one place when they are so flexible, I myself have explained the seatbelt functionality to many of such ...
Starbucks, or for that matter coffee / tea take-away glasses of *any* vendor in USA has a warning: "Contents hot - please be careful while drinking" or something like that. The person who came up with this idea should be given a Nobel prize in Physics, don't you think?
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Old 7th October 2014, 15:10   #66
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Default Rear Selt Belt Install - OHC 2003

Mod Note : Please do NOT use acronyms (e.g. ANHC, T-Fort) when referring to cars. You are ONLY permitted to use the full Make & Model name for cars.

Hi,
My 2 year old niece will be coming to visit very soon. I have a 2003 Honda City. I wanted to get rear seat belts installed in the car. I was wondering if there is a ready mechanism provided in the car to this end or will there be some modification required?

What would the estimate cost of the installation be?

Thanks in advance,

Sibot

Last edited by GTO : 8th October 2014 at 14:55.
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Old 8th October 2014, 08:48   #67
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Default Re: Rear Seat Belt Install - OHC 2003

Mod Note : Please do NOT use acronyms (e.g. ANHC, T-Fort) when referring to cars. You are ONLY permitted to use the full Make & Model name for cars.

AFAIK the 1st-gen City came with rear seat belts! One for each side and one for the center. How come yours does not have one? Was it removed for any seat cover work or something?

I have a 2000 and a 2002 vtec, both of them have rear seat belts. I am yet to come across a City (1.3/1.5/1.5vtec) which doesn't have rear seat belts installed!

Last edited by Aditya : 9th October 2014 at 12:21. Reason: Typo in title
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Old 8th October 2014, 10:06   #68
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Default Re: Rear Seat Belt Install - OHC 2003

IMO the City 1.3 DX didnt come with rear seat belts. A friend has the same and it doesnt have seat belts on the rear.

OT Sir you have 2 VTEC's . I am jealous that you own them in the best available colours, Black and Heather mist.

Last edited by Aditya : 9th October 2014 at 12:21. Reason: Quoted post edited
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Old 8th October 2014, 10:51   #69
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Default Re: Rear Seat Belt Install - OHC 2003

Is it seat belts you are thinking for 2 year old or a child seat that can be strapped into the firm harness on the seat. The child seats may have add on seat belts. All you may need is proper hooks on the rear seat at the adjoining angles to hold the seat firmly.

The seat belts of the type we use for adults aren't comfortable for the kids. Due to the mismatch between height of kids and seat belt heights, you would end up putting the belt closer to the neck of the kid. And that could be risky in a fatal collision. I suggest you to use the car seat with proper harness that straps into the rear seat and has more comfort and safety compared to regular seat belts.

Do read these threads for more ideas -
http://www.team-bhp.com/forum/indian...ght=child+seat (Indian cars to become "Child Seat" friendly from October 2014)
http://www.team-bhp.com/forum/modifi...ght=child+seat ("Child Seat" for Babies & Kids)
http://www.team-bhp.com/forum/modifi...ght=child+seat (Carkoon- Enhanced Safety Child Car Seat)

Last edited by Aditya : 9th October 2014 at 12:22.
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Old 8th October 2014, 15:14   #70
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Default Re: Rear Seat Belt Install - OHC 2003

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Originally Posted by KaandBaaz View Post
IMO the City 1.3 DX didnt come with rear seat belts. A friend has the same and it doesnt have seat belts on the rear.

OT Sir you have 2 VTEC's . I am jealous that you own them in the best available colours, Black and Heather mist.
Buddy, you maybe correct! My friend has a City 1.3 Ex, that model has rear seat belts. Maybe the "Dx" being a lower trim level they did not provide with the belts.

However, retrofitting them should not be a issue. I am not sure of the cost involved though!

Last edited by Aditya : 9th October 2014 at 12:22. Reason: Typo in title
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Old 8th October 2014, 16:19   #71
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Default Re: Understanding Seat Belts : Layman Language

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Originally Posted by ssjr0498 View Post
AFAIK the 1st-gen City came with rear seat belts! One for each side and one for the center.
Quote:
Originally Posted by KaandBaaz View Post
IMO the OHC 1.3 DX didnt come with rear seat belts. A friend has the same and it doesnt have seat belts on the rear.
Well this is funny. After reading your post I inspected the rear seat thorougly of the car and voila seat belts! The Honda City is a 1.3 DXi, it was purchased second hand. The previous owner installed new seat covers and had concealed the seat belts underneath the seat. I have attached pictures for further reference.

What I am not able to understand is that are these belts the airline type that only go around your waist? They seem just that to me but I guess Honda has given a provision for installing the regular upper body seat belts too (see attahced picture for provision).
Quote:
Originally Posted by abirnale View Post
Is it seat belts you are thinking for 2 year old or a child seat that can be strapped into the firm harness on the seat. The child seats may have add on seat belts. All you may need is proper hooks on the rear seat at the adjoining angles to hold the seat firmly.

The seat belts of the type we use for adults aren't comfortable for the kids. Due to the mismatch between height of kids and seat belt heights, you would end up putting the belt closer to the neck of the kid. And that could be risky in a fatal collision. I suggest you to use the car seat with proper harness that straps into the rear seat and has more comfort and safety compared to regular seat belts.

Do read these threads for more ideas -
http://www.team-bhp.com/forum/indian...ght=child+seat (Indian cars to become "Child Seat" friendly from October 2014)
http://www.team-bhp.com/forum/modifi...ght=child+seat ("Child Seat" for Babies & Kids)
http://www.team-bhp.com/forum/modifi...ght=child+seat (Carkoon- Enhanced Safety Child Car Seat)
Thanks for the info and the concern. I have already purchased a Mothercare Toddler Car Seat (9-18kgs) (second hand for Rs.3,000/-, got the seat foam dry cleaned and it's almost new now). I tried to install the seat with the around waist airline type seat belts and it seems to have secured it pretty well. I'll read the links for further information!
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