Finally..PA has actually defined who is allowed to be open
Essential services and sectors include but are not limited to food processing, agriculture, industrial manufacturing, feed mills, construction, trash collection, grocery and household goods (including convenience stores), home repair/hardware and auto repair, pharmacy and other medical facilities, biomedical and healthcare, post offices and shipping outlets, insurance, banks, gas stations, laundromats, veterinary clinics and pet stores, warehousing, storage, and distribution, public transportation, and hotel and commercial lodging.
This applies to all of PA except Philadelphia, which has its own guidelines. Full statement here- Wolf Administration Updates Businesses on Guidance for COVID-19 Mitigation Efforts