They have it in Ohio, but not in Indiana. I use to live in Ohio and it is a pain in the rear end. From what I understand, if your state reaches a certain level of pollution (as judged by the EPA), it is one of the steps you must take or your state loses federal highway funds. Everu year your car must pass a test where your car is run at high idle for a period of time and they mesure the pollution content coming out of your exhaust. If your car does not pass, you can not get a license for the car until you show proof that you corrected the problem. Farm and commercial vehicals use to be exempt, so many people bought pick ups and bought truck licenses just to avoid the mess. I don't know if that can still be done. Many times I had to make an appointment, take off work, and sit while they messed with my car. They also damaged my In-Law's new car.