WHILE WORKING ON THE AIR VALVES TO THE SPRAY BARS LOCATED INSIDE THE CAB OF A WATER TRUCK, A GUST OF WIND BLEW THE CAB DOOR SHUT AND CRUSHED THE EMPLOYEE'S RIGHT HAND BETWEEN THE DOOR EDGE AND THE DOOR FRAME. RESULTED IN DISLOCATING HIS RIGHT HAND RING FINGER AND FRACTURING HIS RIGHT HAND LITTLE FINGER.