[Greenbuilding] PU & adobe

[Bruno M.]

Indeed Tom it's the smoke that kills,

- Polyurethane polymer is a combustible solid and will ignite
if exposed to an open flame for a sufficient period of time.
Decomposition products include carbon monoxide, oxides of nitrogen, 
and hydrogen cyanide:
CO, NOx, HCN  [ 3 (real-)killer gasses ]
Firefighters should wear self-contained breathing apparatus in enclosed areas.

- But on the other hand, CO is found in nearly every house-on-fire, 
by incomplete combution from any hydrocarbon,
and the others will also be found if nitrogen containing products 
like e.g. wool catches fire.

- The PU industrie own info website:  www.polyurethane.org/s_api/index.asp

- Maybe download this 4 page pdf:   Polyurethane Products in Fires: 
Acute Toxicity of Smoke and Fire Gases.
www.polyurethane.org/s_api/bin.asp?CID=936&DID=4041&DOC=FILE.PDF


- PU hardfoam only has a long life if not exposed to sun & rain.
espesially sunlight ( UV-radiation ) will destroy it in a few years.

- About vapor permeability:
www.astm.org/cgi-bin/SoftCart.exe/DIGITAL_LIBRARY/STP/PAGES/STP18498S.htm?E+mystore

Grts
Bruno M.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
At 20:10 6/09/2007, ~Rob Tom wrote:
>On Thu, 06 Sep 2007 08:21:58 -0400, wmdorsett at sbcglobal.net
><wmdorsett at sbcglobal.net> wrote:
>
> > Vadurro, Rob, EMNRD wrote:
>
> >> PU foam is vapor permeable and waterproof, good
> >> characteristics to have, and it seems to stick to adobe (and everything
> >> else!) just fine. I've not heard of any long term problems,
>
>
>I can't take the time to look it up right now but I'm pretty sure that the
>vapour permeability numbers for pee-you foam straddles both sides of the
>"one perm or less" rating which classifies a material as being effectively
>a vapour barrier.
>
>The numbers 0.4 to 1.6 perms come to mind but it wouldn't hurt to check.
>
>So for a 4-inch thickness of pee-you foam (as the OP had mentioned), I
>think that one can safely assume that the foam will not be vapour
>permeable at all.
>
>The problem (WRT fire) with most foamed plastic insulations is not so much
>the potential for flame.
>
>It's the smoke and to a lesser extent, the hazard that is created by the
>molten material dripping onto exposed flesh. I'm not sure if these would
>apply to pee-you foam so it's another thing that should be checked.
>
>In most fires, it's the smoke that kills, not the flame.
>Being burned by molten chemicial goo dripping onto a buildings occupants
>may not kill 'em, but it wouldn't be pleasant either.
>
>--
>=== * ===
>Rob Tom
>Kanata, Ontario, Canada
>< A r c h i L o g i c  at   C h a f f Y a h o o  dot  C a  >
>(winnow the chaff from my edress in your reply)
>_______________________________________________