EE WAS HELPING THE MECHANIC PREPARE THE D11N TO WELD THE LEFT SIDE OF THE HARD BAR. EE RAISED THE DOZER UP IN ORDER TO CRIB UP THE TRACK FRAME. WHILE DISMOUNTING THE DOZER CAB, FROM THE LEFT S IDE, EE SLIPPED, FALLING ONTO THE TRACK FRAME, HITTING HIS HEAD ON THE TILT CYLINDER, SUFFERING A LACERATION TO HIS HEAD. THE SITE CONDITIONS WERE SUNNY, TEMP. OF 25 DEGREES, GROUND FROZEN.