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beware using salt for ef

updated mon 31 mar 97


Monona Rossol on thu 13 mar 97

> There is some recent research out of
> England, published in the latest issue of Ceramic Review magazine,
> indicating that no trace of Chlorine could be found in the gas
> from a couple of salt firings. <

I wonder why people keep reinventing the wheel. There were tons of salt glaze
emission studies in the Brick Clay Record in the 1930's, 1940's, and all the
way up through the 60's if memory serves. There probably are even more
sophisticated studies in the Ceramic Engineering literature--especially
because in most developed countries, large ceramic operations must submit
environmental data.

This is an old hat ceramic engineering problem with no mysteries left for
anyone who wants to look at the data.

> H20, NaCl and HCl are the much more probable components. <

> Combining salt and colorants and applying them to ware is a worthwile
> area of exploration. The small quantities of NaCl involved should
> pose no health risk, to school yards or anyone. If anything,
> airborne release of metal oxides from such a technique would be a
> minor concern but probably not any more of a concern than in the
> firing of many glazes. <

I'm wondering what kind of salt glazing you are talking about that is so
safe. And just how much HCl is it good for you to snort? I remember the
almost explosive force with which the salt fumes and how careful I had to be
not to get a lung full. I remember that cloud of pungent HCl-containing fog
chasing me down the hill away from my outdoor gas kiln. I remember the dead
tree limbs above the stack. This is no project near most school
yards--reform school, maybe.

Monona Rossol, industrial hygienist
Arts, Crafts and Theater Safety
181 Thompson St., # 23
New York, NY 10012-2586 212/777-0062