You can be arrested and charged with a DUI under 75 Pa. Code §3802.
Specifically, 75 Pa. Code §3802(a)(1) prohibits you from driving, operating, or being in actual physical control of the movement of a vehicle after imbibing enough alcohol that you are incapable of safely driving, operating, or being in actual physical control of the movement of a vehicle. Also, 75 Pa. Code §3802(1)(2) prohibits you from driving, operating, or being in actual physical control of the movement of a vehicle after imbibing enough alcohol that your breath or blood alcohol concentration (BAC) is at least .08 percent within two hours of driving, operating, or being in actual physical control of the movement of a vehicle.