AN ACCIDENT CONTRIBUTING TO THE EMPLOYEE'S CONDITION IS UNKNOWN. EMPLOYEE OPERATED A VOLVO L220D RUBBER TIRED FRONT END LOADER. THE LOADER IS EQUIPED WITH AIR SUSPENSION SEAT, A/C & ADJUSTABLE STEERING & OPERATING LEVER POSITIONS. 4 TO 8 HRS/WK EE WAS ASSIGNED MAINTENANCE DUTIES SUCH AS WELDING, MECHANICAL REPAIRS TO CONVEYORS, OIL & GREASE.