[TheForge] Avoiding the Darwin Award while trying to reduce risk

[Kathy]

The following was posted on another group in response to a lot of Chicken Little
type hysterical comments on cadmium content in filler alloys:

It is always necessary to understand the filler materials and fluxes you are
employing; take the case of Cadmium Vs Antimony for instance: Cadmium, like
lead, is toxic in all its forms, which means among other things that you must
use caution when buffing joints where it is present. It is illegal to employ
cadmium bearing
joining alloys on items used for food and drink, or on medical instruments, and
is being replaced in many filler alloys; probably in anticipation of the same
hysteria that surrounded lead use. One of the common replacements for cadmium in
filler alloys today is antimony. But, antimony is also poisonous; it is very
similar to arsenic. Both cadmium and
antimony produce toxic gas when you exceed their boiling points, but antimony's
off-gassing is far worse than cadmium's. In gaseous form, antimony combines with
hydrogen (which boils off of some fluxes, and is also abundantly present in
reducing flames) to form stibine gas, which can be fatal at concentrations as
low as 10 parts per
million.

So, we see that a thorough understanding of tooling and materials is our only
path to safety, and also that reading a product's MSDS before use is more
critical all the time. Substituting products which have been safely used by
professionals for decades can lead to greater risk than is posed by the
originals. Also, not every product can be replaced with an adequate substitute.
Handy and Harmon's Easy-Flow #45 can be traded out for their #560 with only a
small increase in price as penalty. However, Easy-Flow #35 is a capping
(filleting) alloy which has no good silver braze substitute.

There was an episode of Taxi that concluded with Alex, standing outside Elaine's
freshly slammed apartment door, with a kind of stunned look on his face; he had
just automatically declined an invitation from her, and is obviously thinking
what a lunkhead move it was. A drunk who had watched the whole scene, careens by
saying "yup, when you do what you don't understand, that's when you suffer"...
Mikey

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