I posted this to a couple of other threads which you need to be made aware.
Pittsburgh police attend the yearly MPOETC training, so they know open carry is legal. If you're in to civil rights, not just firearms, PA is NOT a "stop and ID" state. You have normally have obligation to provide ID, unless Pennsylvania is in a state of emergency. Make sure you have your CCW license on you at all times.
PA is currently in a "state of emergency." A state of emergency can only last 90 days unless renewed by the governor.
(2013 Proclamation #2.0) Dauphin County Bridge May 9, 2013.pdf
18 Pa.C.S. § 6107: Prohibited conduct during emergency
(a) General rule.--No person shall carry a firearm upon the public streets or upon any public property during an emergency proclaimed by a State or municipal governmental executive unless that person is:
(1) Actively engaged in a defense of that person's life or property from peril or threat.
(2) Licensed to carry firearms under section 6109 (relating to licenses) or is exempt from licensing under section 6106(b) (relating to firearms not to be carried without a license).
(b) Seizure, taking and confiscation.--Except as otherwise provided under subsection (a) and notwithstanding the provisions of 35 Pa.C.S. Ch. 73 (relating to Commonwealth services) or any other provision of law to the contrary, no firearm, accessory or ammunition may be seized, taken or confiscated during an emergency unless the seizure, taking or confiscation would be authorized absent the emergency.
(c) Definitions.--As used in this section, the following words and phrases shall have the meanings given to them in this subsection:
"Accessory." Any scope, sight, bipod, sling, light, magazine, clip or other related item that is attached to or necessary for the operation of a firearm.
"Firearm." The term includes any weapon that is designed to or may readily be converted to expel any projectile by the action of an explosive or the frame or receiver of any weapon.
§ 7301. General authority of Governor.
c) Declaration of disaster emergency.--A disaster emergency
shall be declared by executive order or proclamation of the
Governor upon finding that a disaster has occurred or that the
occurrence or the threat of a disaster is imminent. The state of
disaster emergency shall continue until the Governor finds that
the threat or danger has passed or the disaster has been dealt
with to the extent that emergency conditions no longer exist and
terminates the state of disaster emergency by executive order or
proclamation, but no state of disaster emergency may continue
for longer than 90 days unless renewed by the Governor.