by following the 5 whys analysis technique, it appears that the actual root cause of this accident is "trying stupid shit at home"... (maybe just buy some firecrackers for the reenactment next time? no pressing need to cook them at home Breaking Bad style...)

I did wonder whether his point was that he'd followed all the precepts of his training to the letter, and the dodgy beaker was the unsuspected weak foundation. But then, later in the thread...

> I did a lot of small things wrong, including working at 4am while I was dead tired.

Hmm. Well. Maybe not then?

(As a betting man, I will also bet that this was not the first time that he had done this.)

Yeah, I am going with the general idea that most disasters are really an accumulation of small mistakes, unlikely events, bits overlooked, that just happen to line up, all aided by the normalization of deviance. And it is frightening because each and every one of us is subject to this kind of thing unless we develop an unhealthy-in-all-other-respects obsession with repetitive checking. Familiarity brings contempt for safety procedures.