Any home where children might be present so that pretty much includes any home with a firearm even if you don't have your own children unless you're not going to ever have your grandkids or nieces and nephews into the house... Another almost unenforceable law that will do nothing to make anyone safer.. except for burglars of course and home Invaders. Now they would no longer have to worry about being met by an armed homeowner (if that homeowner was stupid enough to comply)
Wait. A child *could* figure out a combo to a safe.