Black bears are pretty shy of people, you have nothing to worry about. The stories about bears killing people are almost always about grizzly bears, which do not live in Pennsylvania.

Black bears, by the way, can be many different colors, despite their name. If you're still afraid, just be noisy. the most dangerous bear is a cornered bear. It's the wrong time of year for cubs, too, by the way, the cubs would be pretty big by now.