DRIVER CLIMBED ON TOP OF HIS TRAILER AND WAS GOING UNDER A BEAM WHEN HIS MEASURING STICK STRUCK THE BEAM KNOCKING HIM OFF BALANCE. HE FELL ON HIS STOMACH AND THEN SLID UNDER THE FALL PROTECTION HAND RAILS. HE GRABBED THE RAILING BUT WAS UNABLE TO HOLD ON AND FELL ABOUT 8 FEET TO THE GROUND. HE STATED THAT HE WAS OK JUST A LITTLE SORE & DIDN'T WANT TO GO TO THE DOCTOR.