Improving Safety - Shoulder Harnesses & Lap Belt

[Jeff10]

Hi,

Life was sure less complicated before reading more about safe practices that are important to us all.

I don't believe we have ever used the 4-point harnesses in our '71 since we took delivery 4 years ago. When installing new seats last year I got a closer look at the seat belt and shoulder harness installation. The seat belts are bolted through the floor pan. The shoulder belts are wrapped around a horizontal cross brace for the roll cage. The belts around the cross brace aren't secured... they are bolted together and wrapped to make them somewhat secure. The method bothered me enough to think that I should figure out a better way to secure them.

I am attaching some pages from a safety manual I ran across when searching online. It shows examples of proper ways to attach shoulder belts to a roll cage. I'm curious if anyone on the board has comments about the method shown. Another option would be welding tabs on the roll bar.

I believe I also read that the lap belts shouldn't be tied to the roll cage. Depending on the bolt size and some small reinforcement/backing plates, I am trying to understand if lap belt mounting through the floor pan is good practice.

Any thoughts would be appreciated.

Jeff

 

[Hozr]

Find any of the major sanctioning bodies rules for racing and you should be good to go.

HOWEVER, if safety is your primary concern I should warn you that 4 point harnesses will not be found in the manuals as they are inherently not safe....A factory 3 point is better than a 4 point aftermarket.

Look at the competition construction section for details

https://nasa-assets.s3.amazonaws.com/document/document/282/2015_CCR.pdf

 

[Jeff10]

Hi Hozr,

Find any of the major sanctioning bodies rules for racing and you should be good to go.

HOWEVER, if safety is your primary concern I should warn you that 4 point harnesses will not be found in the manuals as they are inherently not safe....A factory 3 point is better than a 4 point aftermarket.

Look at the competition construction section for details

https://nasa-assets.s3.amazonaws.com/document/document/282/2015_CCR.pdf

Thanks for the input and the link.

I looked through the document you provided. It is a little confusing. 11.3.2 discusses 4-point harnesses (depending on their certification) and 15.5 specifically states 5, 6 or 7-point systems.

I'm curious about the factory 3-point system being safer than an aftermarket 4-point... What's the reasoning? (I definitely understand the added benefit of the 5-point system, though.)

(I'm glad you posted... I had forgotten to include the attachments.)

Take Care,

Jeff

 

[Hozr]

For the sake of transparency - I am the regional director for NASA NorthWest hence the link. I am also an SFI certified Technical Inspector. Most sanctioning bodies adhere to SFI or FIA recommendations.

Section 11 of that document is for NON-competition vehicles (street cars, etc). We do not allow 4 point harnesses UNLESS they are specifically approved by an OEM MFG. There are a few BMW's that come to mind that approve 4 point harnesses.

The reason we do not allow 4 point harnesses is they tend to ride too high on the occupant. The lap belt should remain low across the hips and without a submarine strap the shoulders tend to pull the latch mechanism up over the abdomen - NOT GOOD as this result in the occupant sliding under the belts in frontal impacts.

OEM 3 point belts are designed to keep the lap belt low across the hips by allowing some upper torso movement in an impact before the belts lock. Basically the 3 point belt is designed to fold you in half over the lap belt portion. This is also why airbags are so effective. It allows a little upper body movement before cushioning the blow.


Other issues we see with harnesses are:

REALLY bad shoulder strap mounts/angles - One size does not fit all.
Submarine belt over the front edge of the seat cushion instead of through the cushion.
Excessively long webbing.
Belts not threaded through keepers correctly.
Improper mounting of fixed points (Sheet metal screws? Are you F'ing serious!?!?!)

Dates are not generally as important in street cars as competition cars.

 

[Hozr]

Forgot to add, there is a method to install 6 point harnesses in a 4 point system WITHOUT having to cut the seat or add an opening. It basically ends up like a climbing or parachute harness.

 

[Jeff10]

Hi Hozr,

Thanks for the clarification.

My wife and I wear lap belts all the time; but, haven't used the shoulder belts. Right, wrong or otherwise... for the recreational wheeling we do, we very seldom see people on the trail wearing shoulder harnesses (or submarine belts). Not saying that it wouldn't be best to wear 5-point belts to be confident of our level of safety... it's typically not seen for moderate trail running. (Maybe I've just been blind to it.)

The seats we're running do have cuts through the seats and seat covers for the submarine belts, so that isn't an obstacle.

All that being said, is it wrong to consider using 4-point restraints as added protection relative to a 2-point lap belt? I'll do some searching for the submarine belts for our harnesses... just thinking about the interim.

Also... Is it correct to anchor the shoulder belts to the roll cage and lap/submarine belt to the floor pans? (I should go back an study the document before asking... hoping you would know off hand.)

Thanks again.

Jeff

 

[TN1776]

I ran 4-point harnesses for years. A friend who races cars saw them and said something along the lines of not wanting to attend my funeral and then explained much of what is stated in the above links in clear, plain English. He had me sit in the seat and demonstrated some of the issues. It was an eye opener.

I have since switched to a 3 point harness and I have a lot of faith in the system. It locks up in panic maneuvers like it should and is so much more comfortable. Adding to what was stated above, I had never thought much about it but my 4-point harnesses forced me to kind of slouch in the seat, and the lap belt was always riding on my abdomen - two very bad things.

There is only so much that you can do to improve the safety of a 40+ year old vehicle, but some of what people are doing actually makes them worse.

 

[Jeff10]

Hi TN1776,

I haven't done any research into 3-point harnesses, yet... Just curious about installing 3-point harness systems for use in seats with high bolsters on the bottom cushions and how they wouldn't present a problem riding up on my abdomen.

Thanks,

Jeff

 

[Hozr]

4 point is better than 2 point only in that it will damage your legs as opposed to our head in a frontal impact.

As long as the lap belts are reinforced and not just through one layer of sheet metal you should be fine. Even a large fender washer is better than nothing and don't be too concerned about mounting to different surfaces as long as the cage and tub are fairly sound.

One of the biggest issues we see in non-race car mounting is the shoulder belts anchored to the bolts anchoring the rear of the seat (straight down).

This is an interesting search for information regarding mounting, construction, etc :

https://www.google.com/search?q=sea...iQoQTHnYKQDg&ved=0CAkQ_AUoAg&biw=1366&bih=677

Notice the buckle location - Also note he is wearing a 3-point belt. He was not allowed to wear the 4 point to drive (street car) but it was placed to take the picture for threads like these!

Death harness!

There is all manner of FAIL out there and you wouldn't believe what people think is safe or even marginally passable as safe

 

[Jeff10]

Hi Hozr,

Thanks for the additional detail.

I'm still thinking through the options. I'm pretty logical when it comes to thinking something like this through; but, I'm having a tough time understanding that 3-point systems would be comparable to 5-point (or 6-point).

I think a lot of people take for granted that when they buy a vehicle with belts installed, that they are safe. Having thought through this more, and reading your replies and other information on the Internet, I can see the deficiencies of running the 4-point belts. We don't do any extreme wheeling, although roll-overs aren't limited to extreme crawling. My biggest motivator after thinking this through is the drive to and from the trail head. 55 to 65 mph would really put the restraint system to test.

You guys have convinced me that 4-point harnesses should be avoided. I have a few inquiries out regarding buying the anti-submarine belt that will work with the Corbeau 4-point camlock that we already have. (I found them for Simpson; but, nothing yet for Corbeau. I wouldn't think that the two would be interchangeable... but, who knows.) If I can't find the anti-submarine belt, I'll be buying new 5-point harnesses. I will consider the 3-point after I get a chance to look at the mounting options in the Bronco.

Your other points (including the anchor position of the shoulder straps) is well taken.

(With your experience, do you have a preference for Simpson over Corbeau, or maybe another option?)

Thanks again.

Jeff

 

[70_Steve]

Is there a safe way to use a 5-point harness, say, for every day driving, without attaching all 5 straps?

Several years ago I was ready to buy a 5-point harness, but talked to one of the vendors, and after asking about how I use the Bronco, he talked me out of a 5-point. The point made was that, yes, the 5-point harnesses are very save, bur OMG, what a PIA to fasten every time you get in and out of the Bronco! And if you don't fasten the shoulder belts, you now have them digging into your back. Because of that conversation I run a 3-point.

 

[Jeff10]

Hi Steve,

Is there a safe way to use a 5-point harness, say, for every day driving, without attaching all 5 straps?

Several years ago I was ready to buy a 5-point harness, but talked to one of the vendors, and after asking about how I use the Bronco, he talked me out of a 5-point. The point made was that, yes, the 5-point harnesses are very save, bur OMG, what a PIA to fasten every time you get in and out of the Bronco! And if you don't fasten the shoulder belts, you now have them digging into your back. Because of that conversation I run a 3-point.

Good to see you!

Thanks for the input.

I agree... using a 5-point would be a pain all of the time.

I'm hoping that someone who has experienced a roll-over or another type of accident will chime in. Specifically... anyone with a 3-point setup that wishes they would have gone with something different.

This wasn't such an easy topic.... sorry to complicate things.

Thanks,

Jeff

 

[ScanmanSteven]

Jeff,

We have a 3 point system, front and rear and really like it. The system is from a 2 door Explorer. The front anchor points are the original seat belt holes with the shoulder harness anchor on the rollcage, adjusted for height between Janice and I, with the cage tied into the frame. Rear harness are both at the same height, but not bad. I went with the 3 point because of leaning out to see where I'm going or been, with the others you're locked in your seat or don't use them as you need to move a little. In a rollover, I think the more locked in you are the better.

 

[Hozr]

Sorry for the confusion, but in MOST circumstances 5-6-7 point is better (more secure) than 3 point or OEM. I try not to use the phrase "safer" because nothing is inherently safe in what we do! If you want safer buy a new car with 14 airbags and crumple zones.

I'm not going to lie and act like I haven't run without my shoulder straps on. I had a FFR Cobra Replica (5 point simpsons) and the shoulder straps were a complete pain in the ass all the time and fairly uncomfortable at others. There were many times I ran with just the bottom 3 belts and took the risk of bonking my head on the wheel if it came to it. I also drove accordingly.

For extreme wheeling harnesses will keep you secure you just can't move around very much. Everything need to be within arms reach.

Again, I think 3 point belts are just fine for the way I drive the bronco.

 

[Hozr]

I've seen many rigs that run both harnesses and a 3 point setup for the best of both worlds. I may do something similar down the line but I'm getting too old to go rock bouncing anymore!

 

[Jeff10]

Hi Hozr,

I've seen many rigs that run both harnesses and a 3 point setup for the best of both worlds. I may do something similar down the line but I'm getting too old to go rock bouncing anymore!

I contacted Corbeau and they suggested looking at their 3-point retractable harness. Here's a link:

http://corbeau.com/other/harness-belts/3-point-retractable-harness-belt.html

Any thoughts?

Corbeau also offers a more traditional 3-point belt system which I originally emailed them about. The harness above is what they recommended. The absence of the anti-submarine belt is my only real concern.

Any advice you'd like to offer would be appreciated.

Thanks,

Jeff

 

[Hozr]

It's hybrid 3 point / 4 point harness. It functions the same as a traditional OEM 3 point belt where the top gives a little first (due to the retractor) to keep your hips in the seat. The only difference is it captures both shoulder instead of one which is much more beneficial in off roading applications. OEM's have been playing with this for a while but it's been hard to get the public on board (surprise!). Many aircraft also use a similar system (2 retractors as opposed to a Y belt). It's a proven and reliable setup and better than a static 4 point system as long as you can mount it within MFG's guidelines. Really a decent compromise between a harness/belts.

-Andy

 

[Jeff10]

Hi Andy,

Thanks for the quick feedback.

I'll take a look at their mounting recommendations before ordering.

It sounds like you think it might be looking at more closely at Corbeau setup. Is that correct?

Thanks,

Jeff

 

[Hozr]

Hi Andy,


It sounds like you think it might be looking at more closely at Corbeau setup. Is that correct?

(E.T.A.) --- I already have height adjustable 3 point belts mounted to my cage ---

??? Not sure what that's asking. Personally If I go to harnesses I'm considering adding a harness bar and 6 point belts mounted in the 4 point "parachute" configuration like to Schroth Profi ""F" (page 16) - Heres some great info

http://www.schrothracing.com/sdocs/2009_Competition_Instructions.pdf

 

[Jeff10]

Hi Andy,

(E.T.A.) --- I already have height adjustable 3 point belts mounted to my cage ---

??? Not sure what that's asking. Personally If I go to harnesses I'm considering adding a harness bar and 6 point belts mounted in the 4 point "parachute" configuration like to Schroth Profi ""F" (page 16) - Heres some great info

http://www.schrothracing.com/sdocs/2009_Competition_Instructions.pdf

Sorry... my wording wasn't clear.

I'm not trying to put you in a trick box.

In earlier discussions on the thread I understood that running a traditional harness system, such as Corbeau's, but only using 4-points (2-shoulder and 2-hip) was really bad practice because of the possibility of sliding forward without an anti-submarine belt. What I now understand is that design of the 3-point Corbeau system with its ability to let the shoulders move forward slightly will reduce the possibility of the lap portion of the system riding up on the abdomen.

I'm not looking for any type of official opinion... only your thoughts on the safety of the Corbeau system. (Or to be more direct, do you see anything that you would be uncomfortable with if it were you?) I agree that a 5-point or 6-point system would be safer... it's use would have more limitations.

Sorry to make this so difficult... just trying to understand your thinking based on experience and education.

Thanks again.

Jeff