I need some advice on this problem. I work with a guy who lied his
way into the job and has barely any real idea of what he is doing!!
the follow is a work order I saw of his.

"Breaker kept tripping put in another 20amp breaker and it tripped
instantly. Found a 30Amp breaker and installed it. circuit now
working"

This Idiot took a 20amp breaker and installed a 30amp in it's place.
Know I am not a know it all but I do know that a 30amp breaker calls
for 10awg wire. This from the same idiot who said he lead a team of
guys who traveled around changing ballasts and he was asked to change
a ballast and he stood on the ladder for 1 hour trying to figure out
how to do it!!!!

So my question is How Dangerous is this that he installed a 30amp
breaker where a 20amp breaker came out of?