Heidi Haugen on sat 17 nov 01
thanks for the posts, to clarify more....i know the tricks for
attempting to decontaminate an electric kiln. my question is
simply....will pots fired to earthenware temps in a lead contaminated
environment be subject to lead contamination knowing that lead does not
volatize until cone 6?
thanks again,
heidi haugen
John Hesselberth on sun 18 nov 01
on 11/17/01 9:44 PM, Heidi Haugen at redhat@DIGISYS.NET wrote:
> thanks for the posts, to clarify more....i know the tricks for
> attempting to decontaminate an electric kiln. my question is
> simply....will pots fired to earthenware temps in a lead contaminated
> environment be subject to lead contamination knowing that lead does not
> volatize until cone 6?
They well could be. Only testing will tell. If the lead can move from the
lead glazes to the wall of the kiln at earthenware temperatures it certainly
can then move back from the wall of the kiln to other pots. Lead oxide
melts at 1631F. Any time something is in its liquid form there will be a
few molecules of it in the gas phase. The farther above the melting point
the higher this partial pressure of lead oxide will become. Will it be
enough to give a measurable concentration of lead on the surface of the pot?
Don't know. But I would suggest that most of what lead does move to the pot
will be right on the surface because it will not have started moving until
the glaze is sealed over.
Regards,
John
Web site: http://www.frogpondpottery.com Email: john@frogpondpottery.com
"The life so short, the craft so long to learn." Chaucer's translation of
Hippocrates, 5th cent. B.C.
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