WHILE WEARING MY SEAT BELT WHICH I ALWAYS CHECK TO BE SURE IT IS FASTENED I FELL ASLEEP AT THE WHEEL. I HIT THE LEFT BARRIER AND JERKED THE WHEEL. THAT IS ALL I REMEMBER. WHEN I WOKE UP THE CAR WAS UPSIDE DOWN AND I WAS LAYING ON THE ROOF ON MY STOMACH FACING FORWARD. THE SEAT BELT CAME UNBUCKLED AND THE AIR BAG DID NOT DEPLOY. IT APPEARS I WAS THROWN INTO THE EMPTY PASSENGER SEAT AS IT WAS BROKEN. I AM UPSET THE BELT CAME UNBUCKLED. THE CAR WAS A 1999 FORD CONTOUR SE. I HAD NO BUCKLE PROBLEMS IN THE PAST. *JB