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mason stains contain

updated mon 16 nov 98


Monona Rossol on sun 15 nov 98

---------- Forwarded message ----------
Date: Thu, 12 Nov 1998 02:29:20 EST
From: Bob Wicks
----------------------------Original message--------SNIP

Dear Bob,

Good job and sooooo close. But I have a couple of fine points to add.

> Now this is what I would recommend for you to consider. Ask your suppler to
> furnish you with the MSDS sheets (Materials Supply Data Sheet) for each of
> the Mason stains that you use. According to law they must honor this
> request. <

If you are an employer or an employee, they must honor it. Ordinary
consumers can only demand them in states that have consumer right to know

> On this sheet they must describe in detail the contents and
> percentage of the material in question.<

At this point, they can call the material "proprietary" or "trade secret" and
deny you access to the composition. If they do, however, the have to be able
to prove they are using these chemicals in some unique new way that they
developed at significant cost and that their competitors would have an
advantage if they knew. This exemption usually wont work for companies that
buy their materials from other companies and repackage.

The percentage is optional, but good MSDSs have them.

> At this point you will have the most accurate information available. Your
> next decision will be the course of action you will take. In the 1970s the
> accepted amount of lead release was 7 PPM and shortly after that research
> revealed that any release is not to be tolerated. <

You are confusing release from finished pottery from release from unfired
glaze materials. There is no release requirements related to unfired glazes
or glaze ingredients. Only that appropriate warnings be there.

> California is one state that will not allow any lead release and there are
> several other states that are following suit. <

They have set the limit for cups and hollowware at 0.1 ppm--which is almost


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