In addition, a location providing 15 or more parking spaces for the vehicles included in the law such as an attraction, stadium, etc. also need a sign indicating idling restrictions. Here is the wording in the law and what PBA has researched:

An owner or operator of a location where vehicles subject to this act load or unload, OR a location that provides 15 or more parking spaces for vehicles subject to this act shall erect and maintain a permanent sign to inform drivers that idling is restricted in this Commonwealth, as specified in 67 PA. CODE Section 212.101 (A) and (B) (relating to official signs).

Obtain a copy of the PennDOT Idling Sign Specifications.