EE WAS ASSEMBLING THE RIGHT SIDE ENGINE COVER ON A DOZER. HE HAD USED A COME-A-LONG TO LIFT THE COVER UP ONTO THE DOZER. THE COVER SHIFTED AND BUMPED HIM. THIS CAUSED HIM TO STEP BACKWARDS. HE FELL BACKWARDS AND FLIPPED OVER THE DOZER ONTO THE FLOOR. THIS RESULTED IN A BROKEN FEMUR IN HIS LEFT LEG.