72 Pa. Stat. § 4724
The following words and phrases when used in this act shall have, unless the context clearly indicates otherwise, the meanings given to them in this section:
"Deteriorated property." Any industrial, commercial or other business property owned by an individual, association or corporation, and located in a deteriorating area, as hereinafter provided, or any such property which has been the subject of an order by a government agency requiring the unit to be vacated, condemned or demolished by reason of noncompliance with laws, ordinance or regulations.
"Improvement." Repair, construction or reconstruction, including alterations and additions, having the effect of rehabilitating a deteriorated property so that it becomes habitable or attains higher standards of safety, health, economic use or amenity, or is brought into compliance with laws, ordinances or regulations governing such standards. Ordinary upkeep and maintenance shall not be deemed an improvement.
"Local taxing authority." A county, city, borough, incorporated town, township, institution district or school district having authority to levy real property taxes.
"Municipal governing body." A city, borough, incorporated town or township.
72 P.S. § 4724