Bead seat/Foam seat flammability

[Bill Manofsky]

Has anyone taken a sample of the foam from a bead seat and/or a foam seat and tried to burn it?

I hear the foam in a bead seat is self extinguishing....what does that mean?..... that it just chars....or actually ignites and then goes out.

I just tried a sample of the two part exapanding foam and it burns like gasoline.

I also read SFI 45.2. It says in 2.3...."After-flame time: The time an object continues to flame after the thermal load is removed." and in 6.1.2, "the after flame time shall be ten seconds or less. Additionally, no melting or dripping may occur."

[Rick Kirchner]

when I did foam seats I had them covered with rhino liner. Since I'm big the seats have thin sections and very little strength. The rhino liner made them pretty heavy, but very durable and the urethane has to get pretty hot to burn. You do have to grind them down quite a bit because the rhino is about an eighth of an inch thick.

With the bead seats I cover them with thin kevlar and then nomex, gotta burn thru both to get at the beads.

When you are carving the foam seats wear a tyvek suit and a face shield. The dust particles from the foam are as sharp as glass. When you are done, go outside, have your wife put on some safety goggles, and use an air hose to blow you off before you get out of the suit.

[Bill Manofsky]

when I did foam seats I had them covered with rhino liner. Since I'm big the seats have thin sections and very little strength. The rhino liner made them pretty heavy, but very durable and the urethane has to get pretty hot to burn. You do have to grind them down quite a bit because the rhino is about an eighth of an inch thick.

With the bead seats I cover them with thin kevlar and then nomex, gotta burn thru both to get at the beads.

When you are carving the foam seats wear a tyvek suit and a face shield. The dust particles from the foam are as sharp as glass. When you are done, go outside, have your wife put on some safety goggles, and use an air hose to blow you off before you get out of the suit.

Yes, I was thinking the same thing. If you cover it in Nomex, the theory is that any fire will not get to it.

The two part foam is good for making a body mold for then making a fiberglass seat.

[BorkRacing]

Yes, I was thinking the same thing. If you cover it in Nomex, the theory is that any fire will not get to it.

The two part foam is good for making a body mold for them making a fiberglass seat.

Which also burns readily!

[jrh3]

Yes, I was thinking the same thing. If you cover it in Nomex, the theory is that any fire will not get to it.

The two part foam is good for making a body mold for them making a fiberglass seat.

And how how long is a single layer nomex suit good for in a fire? 15 sec?
A single layer of nomex may not be much protection for the foam (or body parts)
For the seat taping enthusiasts, the aviation industry has fire retardant "duct tape"

[Bill Manofsky]

And how how long is a single layer nomex suit good for in a fire? 15 sec?

From http://sfifoundation.com/article-1/

SFI Rating	TPP Value	Time to 2nd Degree Burn
3.2A/1	6	3 Seconds
3.2A/3	14	7 Seconds
3.2A/5	19	10 Seconds
3.2A/10	38	19 Seconds
3.2A/15	60	30 Seconds
3.2A/20	80	40 Seconds

....and you can still bake like a potato.

[TimH]

....and you can still bake like a potato.

or poach like steamed broccoli.

[Rick Kirchner]

gentlemen, let's not forget that setting a material on fire is much different than creating a burn on human tissue. with most foams the fire is not what will get you. they outgas cyanide when they burn (I used to work in a foam fabricating facility that burned and the casualties were all from the fumes). Even the stuff used in furniture burns. The only requirement is that it extinguish when the flame is removed.

[S Lathrop]

I would hate to think that anyone would forego the proven benefits of a bead seat because of the risk of fire. In nearly 50 years of working with race cars, I have seen very few fires that resulted in any injuries. I have however seen hundreds of high impact situations where the benefits of bead seats are repeatedly demonstrated.

The worst crash I ever had as a driver was in a Titan Mk6 FF at the bridge turn at Road Atlanta (there was a real turn there at one time). I went into the bank at very close to the same speed I was approaching the turn. The impact almost broke the car in half through the cockpit. That car had hot water in the upper frame rails, hot oil in the lower frame rails and a fuel cell that just sat in the frame and partially surrounded the seat. The impact crushed the fuel cell and blew the filler fitting out of the cell and filled the seat with fuel. I needed assistance to get out of the car. The car ended up in the middle of the track on its side. I got out uninjured, except for a rash from sitting in gasoline, and I attribute that to my seat.

I had replaced the fiberglass seat with a formed and welded aluminum seat that I sat in without padding. I made the seat myself. There are not a lot of people who can build the type of seat I had but if fire is really that a big a concern then that is what you should do, a form fitted aluminum seat.

[Jerry Kehoe]

My March F3000 chassis is so small it is not possible to pour a seat. So to add some measure I added 3/8 stiff foam on the butt and lower back area from a camping pad. Not much but at least offers some resilience instead of just the tub. Too bad in those days there wasn't a rule package that spelled out a realistic cockpit dimension. My RT4 and 802 March had plenty of room to create a decent seat and if you have the room you should make one. It would be nice to know if a thin (3/8 to1/2") true non resilient foam is available anywhere that could be used.

[Bill Manofsky]

[QUOTE=S Lathrop;567017]I would hate to think that anyone would forego the proven benefits of a bead seat because of the risk of fire. In nearly 50 years of working with race cars, I have seen very few fires that resulted in any injuries. I have however seen hundreds of high impact situations where the benefits of bead seats are repeatedly demonstrated.


Watch the video. This is the scenario I fear. The car is inverted and the driver is trapped underneath with gasoline pouring out. It would not be good that the seat is also flammable too...

https://www.youtube.com/watch?v=OYY9HCN1Euw

[S Lathrop]

[QUOTE=Bill Manofsky;567021]

I would hate to think that anyone would forego the proven benefits of a bead seat because of the risk of fire. In nearly 50 years of working with race cars, I have seen very few fires that resulted in any injuries. I have however seen hundreds of high impact situations where the benefits of bead seats are repeatedly demonstrated.


Watch the video. This is the scenario I fear. The car is inverted and the driver is trapped underneath with gasoline pouring out. It would not be good that the seat is also flammable too...

https://www.youtube.com/watch?v=OYY9HCN1Euw

The car in the vido was older than the one I had my big moment. I was lucky that there was nothing to ignite the fuel. I wonder how good a condition all the components were in in that car. When that car was built, fuel cells were not common.

A few years before my Atlanta incident I did a wall slapper in a FV, high impact. Nearly 45 years later I still have place on my upper thigh where I have no feeling as a result of that crash. Bead seats were not thought of back them. But Had I had a bead seat or and aluminum seat like I had for my Titan, I would not have the issue today. Also I was back on the track that afternoon with the car. I only had to change the wheels that contacted the wall.

Two things to consider, the probability of a fire in a crash against the probability of a high impact crash without the protection of a bead seat. My experience says that the protection of a bead seat will be called upon many more times than protection from a fire. But each driver has to make that decision for him/her self.