Dear OSB-Pros & Cons
I would like to have a completely natural structural board instead of
OSB, but we didn't find a board with the same advantages and a
similar price.
But we tried to look very carefully on OSB, avoided it in the
beginning, but as the OSB Top 4 boards came on the market with
emissions just 1/10 of OSB 3, we decided to use it, until we have a
better material.
There are a lot of tests made for Egger Eurostrand OSB (Top 4) by
serious institutes, which show, that... (if you want all the details,
the complete document is available on the net):
* For the production of OSB EURO TOP only raw materials are used which
correspond to the recommendation of the Commission of BFR plastics
for food packaging: XLV, "Networked polyureas as binders for wood
chips, etc."
* The PUR glue in OSB Top 4 is completely formaldehyde-free.
* yet, there is (natural) formaldehyde in the wood.
* Emission standards EURO OSB 4 TOP and OSB 8000 are below 0.05 ppm
formaldehyde (= equilibrium concentration in the test area) and are
harmless for health.
Formaldehyd measuring point: WKI Fraunhofer Wilhelm-Klauditz-Institut,
Prüf-, Überwachungs- und Zertifizierungsstelle, Braunschweig
- OSB/2: 6,4 mg/100 g atro (10 mm) + 6,5 mg/100 g atro (15 mm)
- OSB/3 : 3,9 mg/100 g atro (10 mm) + 3,1 mg/100 g atro (18 mm)
- OSB TOP: 0,4 mg/100 g atro (12 mm) + 0,3 mg/100 g atro (22 mm)
- OSB 8000: 0,5 mg/100 g atro (25 mm) + 0,2 mg/100 g atro (30) mm
* MDI and other isocyanates:
measuring point: Wessling - Beratende Ingenieure GmbH, Altenberge
Results: in accordance to RAL UZ 76 and NIOSH (P & CAM 142).
The emissions of MDI and other isocyanates were below the detection
limits of analysis. The requirements of RAL-UZ 76 for MDI emissions
are fulfilled.
* Smoke toxicity [ in case of fire or burning the boards ]
Measuring point: University of Osnabrück, Prof. Dr. Lechner IMFE
Materials Results: The results after DIN 53 436 show that the boards
are practically free of chlorine compounds and sulfur compounds.
Hydrogen cyanide, HCN, was below the detection limit. The gaseous
emissions when burned correspond largely to the emissions caused by
burning natural wood.
And so on...
The German magazine Ökotest (which is a relyable ressource, I think),
stated in 2001 for OSB-boards (at this time OSB Top 4 didn't exist,
so the results for OSB Top 4 are again much better):
"In general, OSB keep, what is promised by them. Five out of seven
tested products are "very good" or "good", in only two products of
the manufacturer Kronospan we found several shortcomings.
The result of the sawing tests were encouraging: In no case
isocyanates were found. The consumer can be certain that the PU glue
does him no harm. For the environment, it is still not without
problems.
Good news also at the formaldehyde measurement. Only one product
outgassed after three days more than 0.05 ppm of the the classical
pollutant. After 28 days all products were well below this limit and
thus fulfill the requirements of the environmental label Blue Angel -
for low emissions. This proves that OSB panels have a significantly
lower pollution potential.
Mit lieben Grüßen
Herbert Gruber
--
asbn - austrian strawbale network
Österreichisches Netzwerk für Strohballenbau
3720 Ravelsbach, Baierdorf 6
Email: asbn@baubiologie...
http://www.baubiologie.at
--On Tuesday, December 7, 2010 10:11 AM +0100 Kurt235@yahoo... wrote:
Formaldehyd is a naturel product contained in wood.
There are no formaldeyd free OSB´s (wood).
After "they" found out how bad formaldehyd is, "they" changed the
clue to PU-clue. But this clue contains isocyanate... THat PU-clue
is worse...but most people just don´t know! As a building biologist
i wouldn´t use OSB´s in my home!
I haven't been able to find any references to formaldehyde in
(natural) wood. In all the regulatory documents that I looked at,
formaldehyde was only discussed as an additive to wood products.
Can you tell us more about the concentrations in natural wood, Kurt?
From my searches, it looks like the researchers considered the
naturally occurring levels of formaldehyde in wood, if any, to be
too low to mention. In contrast, there is much discussion of the
amount of formaldehyde added to wood products, and the health risks
that might be associated, even at very low concentrations. There
are also a number of composite wood products labeled as
"formaldehyde-free", which may contain other dangerous chemicals.
Derelict
Derek Roff
Language Learning Center
Ortega Hall 129, MSC03-2100
University of New Mexico
Albuquerque, NM 87131-0001
505/277-7368, fax 505/277-3885
Internet: derek@unm...