First off, there's no such thing as a "CCW from Pa." Pennsylvania issues a License to Carry Firearms (LTCF). An LTCF is required to:
a.Carry a handgun, short-barreled rifle or short-barreled shotgun concealed.
b. Carry one of the above, loaded or unloaded, accessible, in a vehicle.
c. Carry one of the above, open or concealed, in Philadelphia.
d. Carry one of the above during a declared state of emergency.
I believe the second reason stated is the one you're looking for.