SFI "single point of relese" - a new twist

[Knestis]

http://us.st11.yimg.com/us.st.yimg.com/I/wescoperformance_1979_629683.jpg

From http://wescoperformance.stores.yahoo.net/r...point-harnesses (http://wescoperformance.stores.yahoo.net/racingbelts.html#5-point-harnesses)

Sternum Strap for Seat Belt SystemSternum Strap for Seat Belt System.
This Sternum Strap can be added to any model racing shoulder harness that we carry. (Photo shows it with 50516 roll bar mount shoulder harness).

http://us.st11.yimg.com/us.st.yimg.com/I/wescoperformance_1979_471716.jpg

This system is designed to hold the harness together under impact.

Just add this sternum strap to the shopping cart as well as the shoulder harness that you would like to buy, and we will customize the harness by attaching the sternum strap to the harness. And yes, it maintains its SFI rating and the dated SFI tag is attached.


Oh, really??

K

[JohnRW]

Does SFI discuss "sternum straps" in 16.1 (Driver Restraint Assemblies) or 16.5 (Stock Car Driver Restraint Assemblies) ? That's an interesting question.

Is the manufacturer taking some liberties, or do 16.1 or 16.5 allow sternum straps ?

[Gary L]

There may be others, but Impact Racing sells the same type device. Unfortunately, their catalog doesn't address it's effect on the harness' SFI rating.

[Grumpy]

The issue is who requires "single point", SFI rating or the racing organization? I would guess the racing organizatiuon because they say must meet SFI spec AND have single point of release.

In this instance sternum belts would have no impact on the SFI approval.

[JimLill]

add............ some people say they cause problems on severe frontal impact besides.

[Grumpy]

add............ some people say they cause problems on severe frontal impact besides.
[/b]

I have heard this.

I am not for nor against sternum belts as I have not researched the issue..

[Knestis]

...but it's COMPLETELY disingenuous of SFI to say, "That extra pull on a cord makes the Isaac SO dangerous that we just can't allow it," when they are willing to certify a harness that requires an extra action to undo it.

We keep coming back to the egress issue as the rationale for the architecture restrictions in 38.1. Evidence suggests that egress is not important enough to SFI for them to address across the board - only as it might allow alternate designs into the SFI-allowed H&N market. That's arbitrary in the extreme.

No wonder Gregg gets pissy sometimes. The word games and intellectual dishonesty are amazing!

Jim - Have you researched the issue of the dangers presented by the Isaac pin release mechanism more or less than sternum straps?

K

[lateapex911]

..

No wonder Gregg gets pissy sometimes. The word games and intellectual dishonesty are amazing!

K [/b]

Not to mention that, years ago, I remember him posting that he had been in contact with SFI and had gotten the "Talk to the hand" kind of response, LOL.

[gsbaker]

...... some people say they cause problems on severe frontal impact besides.
[/b]
You should see the videos of the harness pull tests.

[gsbaker]

I thought everyone was aware that SFI harness specs allowed for 2 points of release.

Yes, Kirk, this entire rules thing--be they from SFI or sanctioning bodies--has been a joke from day one. Irrational and not worthy of respect.

"Pissy"? :)

[tom91ita]

i thought Neil Bonnet was injured due to a sternum strap when he quit racing for a few years. seems like he had a broken sternum that was attributed to one of those things.

but if you google sternum strap injuries, it is not hard to find something like this:

http://www.circletrack.com/featuredvehicle...fety/index.html (http://www.circletrack.com/featuredvehicles/ctrp_0612_race_car_cockpit_safety/index.html)


3. No sternum straps: When they were first developed, sternum straps were used to keep the shoulder belts closer to the middle of the chest and keep them from sliding off the shoulders. What has been found since then is that these straps are neck injuries waiting to happen.[/b]

or this from http://www.circletrack.com/techarticles/na...ion/index.html; (http://www.circletrack.com/techarticles/nascar_seatbelt_system_tech_inspection/index.html;)


The sternum strap was initially designed to spread belt-tension loads across the chest and include the sternum as a load-dispersing member, but tests have shown it is limited in its effect in a high-deflection (head-on to 30-45 degrees) crash. During side impacts, however, its effectiveness in equalizing shoulder belt loading is increased. There are also questions regarding the mounting of the sternum buckle, including the fact the buckle is close to the driver’s chin and could be an obstacle to exiting the car quickly following a crash.[/b]

[JimLill]

Jim - Have you researched the issue of the dangers presented by the Isaac pin release mechanism more or less than sternum straps?
[/b]

Haven't researched either really, just was told before I ever heard of an HNR that a sternum strap was bad news.

[Grumpy]

I thought everyone was aware that SFI harness specs allowed for 2 points of release.

Yes, Kirk, this entire rules thing--be they from SFI or sanctioning bodies--has been a joke from day one. Irrational and not worthy of respect.

"Pissy"? :)
[/b]

So as I read the SCCA GCR even though the belt is SFI 16.1 it cannot have a sternum belt as it would violate the "single point" rule.

[Gary L]

So as I read the SCCA GCR even though the belt is SFI 16.1 it cannot have a sternum belt as it would violate the "single point" rule.
[/b] I believe that is correct.

[Dave Zaslow]

About three sets of belts ago I had this:

http://www.simpsonraceproducts.com/product...17&prod_id=1585 (http://www.simpsonraceproducts.com/products/product_detail.aspx?cat_id=217&prod_id=1585)

Note that Simpson doesn't mention anything about SFI 16.1, but the SFI tag is shown on the shoulder strap.

My next set didn't have them after I read a caution about the sternum strap on the bellmotorsports site.

I never gave a thought to the second point of release.

DZ

[JohnRW]

...but it's COMPLETELY disingenuous of SFI to say, "That extra pull on a cord makes the Isaac SO dangerous that we just can't allow it," when they are willing to certify a harness that requires an extra action to undo it.
[/b]

If that is the case, then IMO there would be a double-standard.

Anybody got a copy of the SFI belt standards that I posted above (16.1 and 16.5) ? Do they allow sternum straps ? Do they mention sternum straps ?

It's the manufacturer who sews the tag onto the belt. It's the manufacturer who certifies that it meets the standard. I'll ask this again, since it's way too easy to scream "hypocricy" without digging for data: Is this a manufacturer "playing fast and loose", tagging a harness with an SFI tag, or is it a double standard by SFI ?

[Andy Bettencourt]

If that is the case, then IMO there would be a double-standard.

Anybody got a copy of the SFI belt standards that I posted above (16.1 and 16.5) ? Do they allow sternum straps ? Do they mention sternum straps ?

It's the manufacturer who sews the tag onto the belt. It's the manufacturer who certifies that it meets the standard. I'll ask this again, since it's way too easy to scream "hypocricy" without digging for data: Is this a manufacturer "playing fast and loose", tagging a harness with an SFI tag, or is it a double standard by SFI ?
[/b]

It would seem that SFI could never give a sternum strap an SFI tag. Sitting there on the desk it might meet spec but when used as designed, how could it?

I agree with Krik.

[Grumpy]

...but it's COMPLETELY disingenuous of SFI to say, "That extra pull on a cord makes the Isaac SO dangerous that we just can't allow it," when they are willing to certify a harness that requires an extra action to undo it

It does seem odd.


It's the manufacturer who sews the tag onto the belt. It's the manufacturer who certifies that it meets the standard. I'll ask this again, since it's way too easy to scream "hypocricy" without digging for data: Is this a manufacturer "playing fast and loose", tagging a harness with an SFI tag, or is it a double standard by SFI ?

No "fast and loose" here. An additional point of release is allowed by SFI 16.1. It is up to the racing organization to declare single point if they want to require it, and then police it.

[lateapex911]

It apears to me that Wesco is playing with fire. It appears from the pictures and the description, that they are taking a harness and adding the sternum strap. Thats what the description says they do, and if you look at the picture, note that the in car unit is sewn in a different location, and it looks like they have taken the SFI tag and actually removed it and resewn it on their sternum addition! In the other picture, it looks like the SFI tag is in it's original position, with the sternum strap sewn below it.


EDIT: After posting, I see Jim posted at the same time, essentially. While I was searching for the SFI spec, he states the aloowance for multiple points of release exist.

So, I stand corrected. However, I'd be interested in learning HOW the straps are tested. Is it a simple pull to failure? Or does it involve anatomical fitting, etc? I would imagine that the addition of the sternum strap could affect the test if it is more than a pull to failure, and the modifying party is playing with fire.

Another anomoly I spotted while on the SFI site was the 38.1 spec has no dating. Once bought, the item is good forever, according to SFI. But, HANS states the straps must be replaced every two years. How is this actually being handled? Logic suggests that if HANS requires replacement of a part of the item, it must, at some point, fail to meet 38.1 specs, correct?

[Grumpy]

It apears to me that Wesco is playing with fire. It appears from the pictures and the description, that they are taking a harness and adding the sternum strap. Thats what the description says they do, and if you look at the picture, note that the in car unit is sewn in a different location, and it looks like they have taken the SFI tag and actually removed it and resewn it on their sternum addition! In the other picture, it looks like the SFI tag is in it's original position, with the sternum strap sewn below it.

They are asking...beggin' actually, to be sued from here to italy and back. (IMHO)
[/b]

From the Westco web site,

The sternum strap is sewn into your shoulder harness straps (restraint) at the factory, so allow for a few days lead time on your order.

[lateapex911]

Right Jim, it looks like they are taking RJS straps and adding their own part to it. So they're messing around with the SFI tag of another manufacturer, right? or am I confused?

[Grumpy]

Right Jim, it looks like they are taking RJS straps and adding their own part to it. So they're messing around with the SFI tag of another manufacturer, right? or am I confused?
[/b]

I read it as Westco contacts the original manufacturer with a special order so when the original manufacturer makes the belt it includes the sternum belt. Additionally as I read it, the SFI label is attached by the original manufacturer when the complete the special order belts. Westco is just a middlemanbetween the manufacturer and the customer.

Been wrong before.....

[JimLill]

John,

Copies of SFI specs are hard to find........

38.1 was easy http://www.hmsmotorsport.com/docs/SFI_38.1...ecification.pdf (http://www.hmsmotorsport.com/docs/SFI_38.1_Head_Restraint_Specification.pdf)

For belts, I did find this from SFI http://www.sfifoundation.com/seatbelt.html

[924Guy]

My very first set of belts was a 6-pt from RJS - they're local to me, just a few miles away - and it did have a sternum strap. Then I found out those were a bad idea, and I had that phased out when I rewebbed...

[tom91ita]

how does this belt http://www.schrothracing.com/products/Comp...car/16.5-hybrid (http://www.schrothracing.com/products/Competition/nascar/16.5-hybrid) that "sandwiches" or "traps" (my phrases / characterizations) the HANS between two sets of straps
You can specify the standard HANS specific 2"/3" shoulder belts or the state-of-the-art "Double Shoulder" belts that feature the 3" body belt and additional 2" HANS belt.[/b] meet SFI 38.1's requirement that


Direct attachment to react loads to a fixed point or points on a
vehicle structure or restraint webbing will not be acceptable because of the
potential for torso displacements with respect to these points.[/b] bolding mine for emphasis

complete 38.1 at http://www.hmsmotorsport.com/docs/SFI_38.1...ecification.pdf (http://www.hmsmotorsport.com/docs/SFI_38.1_Head_Restraint_Specification.pdf)

it seems to me that "trapping" the HANS between the belts is essentially attaching it to the restraint webbing. it may still be meeting the intent of the single point of release but it is essentially attached to the webbing.

and these belts are SFI 16.5 approved.

tom, who is interested and owns neither Isaac nor HANs and honestly thought these belts were interesting when i first saw them as they keep the driver tight independent of the HANS and figured it must be due to a market demand resulting from the HANS belts becoming dislodged and thought if i get a HANS, these would be the belts to get (before i started actually reading the SFI specs).

[Grumpy]

it seems to me that "trapping" the HANS between the belts is essentially attaching it to the restraint webbing. it may still be meeting the intent of the single point of release but it is essentially attached to the webbing.


[/b]

I see it as attached means just that attached. Captured by or "trapping" is not attached.

But doesn't the Issac really attach to the webbing "seat belts."

[philstireservice]

Wow !!

Never thought of this a being 2 release points. I have Impact Racing belts with ....you guessed it... a sternum strap........can't get out of the thing if you don't release the latch.


They are expired, I think the next set won't have the sternum strap.

Phil

[924Guy]

But doesn't the Issac really attach to the webbing "seat belts."
[/b]

Yeah, pretty much.

[Grumpy]

Yeah, pretty much.
[/b]

Just a question.

If the single point of release issue was removed, would Issac still not be 38.1 compliant because of the attachment issue???

[erlrich]

Just a question.
If the single point of release issue was removed, would Issac still not be 38.1 compliant because of the attachment issue??? [/b] Jim, good question but I don't believe that to be the case, as the Isaac does not attach to a "fixed point or points" on the webbing. It is free to move along the webbing in response to the movement of the driver's torso.

[Quickshoe]

An ISAAC does NOT attach to the belts. It captures the belt between the roller and the c-shaped piece that receives one end of the damper. Not that I think that makes the device any more or less 38.1 compliant. Just trying to keep the facts straight.

[jjjanos]

Nobody knows whether the ISAAC would be SFI 38.1 compliant if the single-point release was removed because the 'standard' is entirely subject. SFI reserves the right to deny any device regardless if whether it meets the standard as published.

Therefore, the 'standard' is not a standard.

[lateapex911]

Right...and if you read the spec, it calls for a "Main unit"...well, the Isaac HAS no main unit.



it seems to me that "trapping" the HANS between the belts is essentially attaching it to the restraint webbing. it may still be meeting the intent of the single point of release but it is essentially attached to the webbing.

and these belts are SFI 16.5 approved.

. [/b]

I would wager that the average Isaac user can pop the pins and be out of the car before the average HANS/Schroth double strap user can wrestle out and be out of the car, but then there I go, being silly and thinking about the big picture again.....

Point being, even if the two average egress times are close, the regulation has been written in such a manner as to limit design, and performance, (ie: true safety) rahter than is such a way as to demand bottom line performance.

[Butch Kummer]

Been away for the weekend, but just to clarify the Neil Bonnett story from early in the thread:

Neil Bonnett actually split his sternum during a particulary bad crash (I believe at North Wilkesboro, but I could be wrong) when the relatively wide-spaced shoulder harnesses held his shoulders back while his body slid forward between them. After recovering he developed and started using the "Bonnett strap", which is similar to this device, to keep the belts together. Subsequent testing has shown that this strap is NOT a good idea!

People give NASCAR grief about being slow to react at times (like the introduction of soft walls), but this is a classic case of creating a worse problem when trying to fix something else.

[924Guy]

Just a question.

If the single point of release issue was removed, would Issac still not be 38.1 compliant because of the attachment issue???
[/b]

Good observation - can you tell I'm not much of a rules nerd?

The issue of "direct attachment" seems like a matter of semantics to me... HOWEVER, more importantly the spec calls out that the (main part of?) device not be "directly attached" to a fixed point or points of the restraint webbing. As the ISAAC rolls freely along the webbing, it's hardly more directly attached to the webbing than the HANS (now with wings, for better protection - sounds like a maxi pad! :P ).

Hardly is not the same as "not" but I think the point should be clear for this specific case. Then again, I'm no lawyer. :dead_horse:

I think it should be clear that the intent of that part of the spec - whether or not this intent is correctly expressed by the wording - is that the device is able to move with the driver; no driver's head will be on a fixed tether to the roll cage or vehicle, either directly or indirectly.



Jim, good question but I don't believe that to be the case, as the Isaac does not attach to a "fixed point or points" on the webbing. It is free to move along the webbing in response to the movement of the driver's torso.
[/b]
Duh, sorry Earl - completely overlooked your response! Then again, looks like I'm not the only one! :014:

[Knestis]

...because of the potential for torso displacements with respect to these points.[/b]

Because the Isaac rollers follow the torso, this shouldn't be an issue. However, one would have to ask SFI for clarification. I have a feeling I know what the response would be, though. :)

K

[tom91ita]

frankly, i do not see a significant distinction between the Isaac rollers gliding along the webbing and two layers of webbing trapping the HANS with the belts i referenced.

in fact, i would think the Isaac better fits the definition of not being "attached" to the webbing, etc.

[Dave Zaslow]

Does the SFI certification of motorsport safety harnesses allow more than a single point of release?

http://www.teamtechmotorsports.com/racingharness/rampac.html

So are they SFI certified?

The Schroth double is pretty interesting in terms of releasing the hans unless the second set of straps is released separately from the first, i.e. plug four shoulder strap tabs into the buckle rather than two. Alas that is not what they are doing as shown in their mounting instructions:

http://www.schrothracing.com/docs/Competit...nstructions.pdf (http://www.schrothracing.com/docs/Competition_Instructions.pdf)

So we find that the FIA specifically allows this type of HANS retention:

http://www.fiainstitute.com/documents/HANS_Guide.pdf (page 4)

But the Schroth system is offered with either FIA or SFI certification. So the question comes back to "Does the SFI certification of motorsport safety harnesses allow more than a single point of release?"

More importantly (for most of us here) does the Schroth design meet the SCCA's GCR requirements? The answer, I believe, is yes. For the drivers restraint system the GCR requires "There shall be a single release common to the seat belt and shoulder harness". as well as FIA or SFI 16.1/16.5 certification. As to any of the systems with a sternum strap, I would say no. There is no requirement that the driver be totally free from any and all attachments to drink tubes, helmet blowers, radio connections, coolshirt feeds, in-helmet data displays, etc. Is there a meaningful difference in having to free a HANS ™ from the Schroth straps and having to pull the pins on an ISAAC ™ ?

Perhaps there should be a requirement that one should be able to bail out of the window-net covered, motionless, upright car within x seconds.

Looking forward to the youtube videos of that test.

DZ

[gsbaker]

Does the SFI certification of motorsport safety harnesses allow more than a single point of release?[/b]
Yes, it does. At least two, possibly three—it's been a while since I've seen it.