Didn't the ValuJet crash happen because an outside vendor loaded mis-labeled (and illegal) Oxygen canisters aboard in the cargo hold?
Quite right, 46Driver.
The drop-down mask, oxygen generators were incorrectly tagged and packed and not recognised as a dangerous good.
This all happened with the ground crew and loadmasters etc... the flight crew were the last "hole in the swiss cheese" (Professor Reasons model)