The primary goal would be establishing unsafe wording in the voting and flagging guides and aids.
I would start with changing the text on the down vote to read:
This answer is unsafe or unusefulnot useful.
Better would be to have the "unsafe" in red.
Also, we could see if a safety category could be added to the flagging interface so people didn't have to type it in other. I don't know if this is an easy code fix, but that could be raised in the main meta if desired and we don't get a comment herhere on the feasibility of custom code for a beta site.
Of course the FAQ will need a safety section - both advising people to be adults and take responsibility for applying information as well as explaining the care taken to let everyone vote on safety and flag for safety.