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cone five glaze questions / duncan clear

updated sat 22 may 99

 

John Baymore on fri 21 may 99

------------------
On using the Duncan lead containing clear:

Is it =22safe=22? Well....... the only way to tell is to do a regular =
program
of representative sample testing of fired wares. In fact, if you are
selling these pieces you better be doing it..... the FDA and the state of
California both have some laws that apply to that situation you are
required to comply with if you sell things.

The manufacturers of the glazes do not offer any indemnification to the
user of the product. That means that they do not accept any legal
responsibility for the use of the product no matter WHAT the label says.
If they are wrong.......you are responsible. Their testing does not
absolve YOU from the requirements of the FDA statutes. So that means that
you are gambling that the glaze is safe........ doesn't matter what the
label SAYS.

The label specifies specific situations for use. If you are doing EXACTLY
that , and nothing but that.....you might be OK on lead release. (The offer
no guarantee.) If you fire faster, slower, hotter, colder, with slips or
underglazes or washes or whatever, or apply it at a different
thickness..... it may not still meet the release standards.

Underglazes, washes, and slips containing copper are a real problem as the
copper compounds lead release issues. The glaze doesn't exist separate of
any decoration under or over it..... they interact.

As to handling it yourself...... it contains lead compounds. Lead
compounds in ALL forms are now known to be bioavailable according to folks
like Monona. So if you don't take appropriate precautions, you potentially
expose yourself to risks.

Should you use it? You have to find out some hard data and then decide
about the risks and the legal issues. Are you willing to comply, take
precautions, or simply ignore the situation? If the answer is =22no=22 to =
any
one or more of those, then you shouldn't use it.

Best,

....................john

John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA

603-654-2752
JBaymore=40compuserve.com
John.Baymore=40GSD-CO.COM

=22Earth, Water, and Fire climbing kiln firing workshop Aug. 20-29,1999=22