Emissions testing not always required

I would like to have an answer to this question:

Why are residents of Blair County required to have emissions inspections for our vehicles while other counties do not? I was so surprised when I purchased a car in Greencastle, and I was not required to have an emissions sticker. I had to come back home and have it checked for emissions and then found out that Bedford County, our close neighbor, doesn’t require it, either.

How is this fair? We all live in Pennsylvania.

Janet Thompson

Roaring Spring