One of those four obviously did something very stupid in that TX room!! I hope that no flammable materials/liquids were being stored in there at the time... or someone's going to be held to account big time!!
We can all speculate as to what caused this, and probably won't be far wrong.
The bottom line is people within our trade often become complacent and forget the dangers associated with something we cannot see.
The old analogy that Electricity is a good servant but a poor master is as true today as the first time I herd it.
Heart goes out to those injured and there families.
I've managed 45 years working with the stuff.
Don't take it for granted.
Its a rabid dog waiting to bite your head off.
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