Employee was using a T-post driver to drive 3/4"" electric metal tubing (EMT) into the ground. As EE was raising the driver, EE went too far up and the tubing came out of the driver cylinder. On the downward motion, EE missed the EMT striking EE's right index finger on the EMT while holding the driver handle. This caused an open wound and broken bone in the tip of EE's finger.