Cohousing-L Mailing List: Fabric-Covered Fiberglass Panels/formaldehyde

[Racheli Gai (racheli]

Thanks, Kai.  That's what I was referring to.
My understanding is that phenol formaldehyde is more stable, and whatever
outgassing occurs, takes place for the most part in the first  few months.
Urea formaldehyde (while it, too, outgasses more in the initial half year
or so) keep outgassing indefinitly.  While people with chemical
sensitivities are advised to stay away from all formaldehyde, the urea
variety is always mentioned as paricularly problematic. R.




>On Monday, July 21, 2003, at 12:57 PM, Howard Landman wrote:

>>> Also, what kind of formaldehyde is it? (Depending on the kind, it 
>>> might do most of the offgassing in a few months, or keep offgassing 
>>> for  years to come).
>>
>>      H
>>       \
>>        C = O         Formaldehyde (all atoms lie in a plane)
>>       /
>>      H
>>
>> Formaldehyde is a very small and simple chemical compound CH2O. There 
>> aren't different kinds of formaldehyde molecule - it's its own mirror 
>> image so there aren't even left- and right-handed forms.
>>
>> The only variants possible would be isotopic (e.g. carbon-13 instead 
>> of carbon-12 or deuterium instead of hydrogen) but that doesn't sound 
>> like what you're asking ... and those would only have a small (a few 
>> percent) effect on outgassing rate anyway (and only because heavier 
>> molecules move more slowly on average).
>>
>>      Howard A. Landman

>The question probably referred not to two putatively different kinds of 
>formaldehyde but to the two different ways in which formaldehyde  usually
>occurs in a product. Here's what the fact sheet on formaldehyde  from the
>National Safety Council says:

>> There are two types of formaldehyde resins: urea formaldehyde (UF) and 
>> phenol formaldehyde (PF). Products made of urea formaldehyde can 
>> release formaldehyde gas; products made of phenol formaldehyde 
>> generally emit lower levels of the gas.

><http://www.nsc.org/ehc/indoor/formald.htm>

>-- Kai.
- 
-----------------------------------------------------------
racheli [at] sonoracohousing.com (Racheli Gai)
-----------------------------------------------------------


_______________________________________________
Cohousing-L mailing list
Cohousing-L [at] cohousing.org  Unsubscribe  and other info:
http://www.cohousing.org/cohousing-L