Re: Vapor Barrier shirt material?

--- In BackpackingLight-F5Bj5G+ccuY@xxxxxxxxxxxxxxxx, BenSimms@xxxx wrote:
 
> Somebody please explain to me the theory behind "Vapor Barrier"
clothing.  
> How would keeping moisture trapped inside your clothes do anything
but make 
> one damp and uncomfortable?  In winter, this could even be dangerous
as it 
> would increrase thermal transmission from your body to the cold air.


Take a look at Jack Stephenson's rather long treatise on this at:

http://www.warmlite.com/vb.htm

You're not alone -- most folks have a hard time with this one at first
<G>. My initial reaction was the same as yours, since the last time I
remembered using vapor barrier suits was when I was trying to cook off
weight for wrestling. 

Surprisingly, one of the reasons for vapor barrier clothing and bag
liners, especially in winter, is to prevent moisture from getting into
your insulation layers where it can become a problem. 

david