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Eric Machemer Posted: Aug 22, 2011 10:15 AM	Open/Closed Appendix X Mike, Could you shed light on why most closed cell spf's are able to pass Appendix X when left exposed while I have not yet seen any open cell spf's that are able to pass appendix X without some type of covering? Thanks.
Posted: Aug 22, 2011 10:48 AM	The reason is because Open Cell foam reaches the flaming stage when exposed to heat much faster than Closed Cell foam. There are a number of reasons this happens. One of the reasons is the fact that there is a lot more air trapped in larger cells in OC foam than in CC. That means Oxygen on the "inside" of cells, which helps materials burn. Also, the thin walls of the large cells cannot hold off heat for long, so that outer skin gets to the point of off gassing pretty quickly, and they are flammable gasses that spread flames. Additionally, CC is a better insulator, so the heat takes longer to penetrate deep into the foam and release flammable gasses. Finally, the fire retardants that are incorporated within the foam are more effective when it is "dense", as with Closed Cell foam. In other words, there is more fire retardant available near the surface of Close Cell foam than with Open Cell foam, which can 'resist' getting to the flaming stage for a longer time. An analogy, for all of the above, is wood. If you put a torch to a 2x8, it will take several minutes to get it flaming pretty well. Now, take very thin sheets of that same wood, and apply the same torch... it goes up in flames almost instantly. Very simiilar effect. Mike
Posted: Aug 22, 2011 09:07 PM	...psst,,,gaco western has a half pound that has passed,,,
Eric Machemer Posted: Aug 23, 2011 06:43 AM	dude, Just went on the ICC website. Gaco ESR's show nothing about passing appendix X for either of their 2 reports (ESR-2478, ESR-3268). Then I went to thier website- still couldn't find anything. Can you direct me to a link that provides documentation? Thank dude.
Dean Nash Posted: Aug 23, 2011 02:40 PM	Sorry, I haven't figured out how to upload it yet and apparently Gaco hasn't either. IAMPO not ICC report number: 0233 Good: 8/2011-8/2012

Author

Comments

Eric Machemer

Posted: Aug 22, 2011 10:15 AM

Open/Closed Appendix X

Mike,

Could you shed light on why most closed cell spf's are able to pass Appendix X when left exposed while I have not yet seen any open cell spf's that are able to pass appendix X without some type of covering?

Thanks.

Posted: Aug 22, 2011 10:48 AM

The reason is because Open Cell foam reaches the flaming stage when exposed to heat much faster than Closed Cell foam. There are a number of reasons this happens. One of the reasons is the fact that there is a lot more air trapped in larger cells in OC foam than in CC. That means Oxygen on the "inside" of cells, which helps materials burn. Also, the thin walls of the large cells cannot hold off heat for long, so that outer skin gets to the point of off gassing pretty quickly, and they are flammable gasses that spread flames. Additionally, CC is a better insulator, so the heat takes longer to penetrate deep into the foam and release flammable gasses. Finally, the fire retardants that are incorporated within the foam are more effective when it is "dense", as with Closed Cell foam. In other words, there is more fire retardant available near the surface of Close Cell foam than with Open Cell foam, which can 'resist' getting to the flaming stage for a longer time.

An analogy, for all of the above, is wood. If you put a torch to a 2x8, it will take several minutes to get it flaming pretty well. Now, take very thin sheets of that same wood, and apply the same torch... it goes up in flames almost instantly. Very simiilar effect.

Mike

Posted: Aug 22, 2011 09:07 PM

...psst,,,gaco western has a half pound that has passed,,,

Eric Machemer

Posted: Aug 23, 2011 06:43 AM

dude,

Just went on the ICC website. Gaco ESR's show nothing about passing appendix X for either of their 2 reports (ESR-2478, ESR-3268). Then I went to thier website- still couldn't find anything. Can you direct me to a link that provides documentation?

Thank dude.

Dean Nash

Posted: Aug 23, 2011 02:40 PM

Sorry, I haven't figured out how to upload it yet and apparently Gaco hasn't either.

IAMPO not ICC
report number: 0233
Good: 8/2011-8/2012

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