Elemental Mercury isn't especially dangerous though. People freak out over the word "Mercury" but forms like that aren't bioavailable for the most part and are reasonably safe. I wouldn't go breathing the fumes for extended periods of time, but holding a pool in your hand in science class isn't going to kill you.
That's why it's a bit frustrating to read stories like this where the cleanup crew goes overboard and racks up tens of thousands of dollars worth of bills for a simple spill.
Not necessarily, since there was nothing to vaporize it. He even shows an old picture he'd taken of it where the drops had sat undisturbed for so long that they had a chance to oxidize.
The techs measured vapor at 37,000 ng/m3 after the first day of cleanup, at which point there was no longer any easily visible mercury. Like water, mercury doesn't need something to vaporize it; you just end up with some vapor as long as there's liquid present.
That's why it's a bit frustrating to read stories like this where the cleanup crew goes overboard and racks up tens of thousands of dollars worth of bills for a simple spill.