There are a lot of assumptions being made about the nature of materials
that are standing in the way of informed practice. We basically do not
know enough about materials to dismiss the potential of any mediums
ability to 'respirate' effectively. As I see it some of the potential
(if any) of breathable wall research is going to be largely based on a
materials innate or enhanced ability to mitigate toxins. One example
that comes to mind is the salmonella studies where the bacteria was
introduced to a plastic and a wood cutting board surface - after 30min.
the bact. was absent from the wooden cutting board and was still going
strong 24hrs later on the plastic.
Most filtration technologies are at this point energy intensive crude
imitations of process that are already embodied in existing or 'natural
materials' - essentially making a door (hole) smaller than the unwanted
guest (pathogen) or making their journey so long and tedious that the
guest dies on the way. This is not to dismiss the use of filtration
technology but the basic research initiative is that our technologies
will only improve as our understanding of materials improve.
Metal ducts and filtration membranes are not innately 'clean' surfaces,
however bright and shiny they might be but their manufactured surfaces
are quite conducive to pathogenic activity (I read recently that some
surgical scalpels are being made from flint knappings and a microscopic
enlargement of the steel versus sheared stone surface was a good
illustration of why)
I am not going to 'agree' or 'disagree' with any of the developing
positions but as I mentioned in my original contributions to this thread
I am not comfortable with the current state of the art and its
implications for the end user. I will continue looking for alternatives
and if I can gather enough information on an alternative process,
technology or material and can distill that into some piece of workable
knowledge I will incorporate that into a project with the hope that its
inclusion will inform our general practice. Please don't dismiss things
because of a 'clean' or 'dirty' feel or because of their distance from
the norm - this is after all a forum that owes its origin to the
practice of 'alternative' or appropriate technologies.
John Salmen
TERRAIN E.D.S
terrain@seaside.net
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