Wes fired this volley in
:

I just finished reading the "bullseye mixture" in the 2nd Machinists
Bedside Reader and am interested in trying the color case hardening
formula described.

It seems the author got a bit of cold feet later on about the use of
barium sulfate.

So the question is how dangerous is trying the method? What should
one do to minimise risk? I see Skylighter has it at reasonable
prices.

Thanks,

Wes


Barium carbonate is not particularly dangerous unless ingested. One
should wear breathing protection, since no heavy metal compound should be
allowed (voluntarily) to enter your body. One notable exception would be
barium sulfate, which is essentially inert in the pH range of body
fluids, and is used for contrast fluoroscopy. (a la "barium enema")

We use roughly 100lb of barium carbonate a month. We use nuisance dust
masks (p-95 rating), and enforce hand washing and clothing dust-off
before eating or smoking.

LLoyd