SFI "single point of relese" - a new twist

[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

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 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

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.

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!

[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/r...ss/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

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.