I have no idea about that. All i know is from a very short newspaper article about 6 years or so ago.
However what about that power washer story?
It says that using a polarized plug would have saved that woman. In this special case it's true, but in any other the insulation of the hot wire could have been faulty too, in that case it'd have actually saved that woman. I thought this is something to think about.
I agree that the missing ground prong was really dangerous.
