No, I'm not American and I'm not terrified of mercury.
My link to asbestos was because they're both dangerous (increasingly) due to length of exposure and are both treated as hazardous material.
I would imagine breathing masks in a "mercury factory" and overalls (not necessarily white), but I didn't immediately think of glassed off areas. Probably rubber gloves, though.
I spent a while searching for mecury factories/refineries/production/etc. but didn't come up with anything worthwhile.
I didn't say "one breath and you are dead", but I can see how my original post might have read more scaremongering that it was meant. I was just saying that I wouldn't put myself in a position of risk if it was unnecessary (and not fun).
To be honest, IANAL but I don't believe Bletchley Park /couldn't/ use mercury due to H&S (which was the reason for my original post), they've probably chosen to do so because of h&s. In other words, why risk exposing people to a potentially dangerous substance if you don't need to? Just go with Turing's idea and use gin!
@Graham Wilson: I'm not going to address every point, but 4 confuses me. OHSA and H&S do not inhibit using mercury, they merely define how to reduce occupational exposure and personnel risk.
OHSA don't even list it in their "highly hazardous" list of chemicals (and yes, I know what a chemical is).