Learning is safer than punishing!
Management by Terror and Fear is never a good plan. Show your people how to behave the only way: by example!
Explain you will always look for the reasoning behind and the answer to the WHY question.
Insist you are not interested in punishment, never, because that will only focus on the wrong side of the improvement cycle. Proudly you say: " I will rather learn ONE safety lesson in stead of catching TEN criminals"!