[TheForge] stainless steel and hexavalent chromium

[Mike Spencer]

> given that the use of hexavalent chromium for corrosion protection
> is banned internationally in 2006 that does nothing for all the
> scrap stainless steel that blacksmiths tend to scrounge produced
> before the ban.

That should be tangential to the tox problem.  It's the chromium
compounds that you can ingest, inhale or get smeared with that seem to
be the problem.  If you dissolve or vaporize the stainless, you get
chrome in a potentially dangerous form.  The ban you mention doesn't
refer to stainless steel, per se, does it?  Just stuff like zinch
chromate primer.  (I wondered why I didn't see it on the shelf any
more.)


> 0) what are the health risks associated with using stainless steel
> nozzles for propane burners?

Well, a nozzle weighs what? 100 grams? And it's 5% chrome? 5 grams.
And you lose, say, 10% of that before you renew the nozzle?  And it
take a year to get there?  So if every bit of 10% of 5 grams (500 mg)
enters the shop as chromium oxide particles in a year?  And if you make
a special effort, you might actually breathe or pick up 1% of
that?

Five milligrams per annum.

Very different from bending over a welding bench 8 hrs a day in an
unventilated helmet, running stainless rod and breathing the fumes or
spraying chromate degreaser mist.

> 2) what have others done to minimize their exposure to the health
> risks/issues/etc associated with hexavalent chromium and stainless
> steel.

Open all the doors when welding (haven't got my exhaust hood put
together yet.)  And use gloves, eye protection and great care when
using potassium dichromate for photo-staining wood.

Isn't it nice that there's no good excuse to have gallon jugs of
mercury around a blacksmith shop. :-)

- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^

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