I have several hammerless doubles on which the safety can be applied in the uncocked state. These all have un-latched top levers which allow the lever to return to center when the gun is fully open. With gun open & lever at center push safety off. Pull triggers to release sears, then release triggers & close gun. With an auto safety gun the safety will reset, with a manual safe it can be left in which ever position desired.

As stated a safety does not 100% guarantee that a gun"Cannot" go off. If someone has a proven instance where safety has "Caused" a gun to fire would like to see the evidence.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra