EMPLOYEE ALLEGES HE WAS STANDING ON TOP OF CEMENT HOPPER WHEN THE SWITCHMAN TOLD HIM HE WAS GOING TO COUPLE THE CAR HE WAS ON. HE SAID THE CARS COUPLED UP TOO HARD AND JUST ABOUT KNOCKED HIM O FF THE CAR. HE WAS WEARING HIS FALL PROTECTION AND HOLDING ONTO HIS SAFETY LINE.