What was found
FLT 583. DECLARED AN EMERGENCY AND DIVERTED DUE TO LOST OF PRESSURIZATION AT 38,000 FT. THERE WAS AN AUDIBLE POP FOLLOWED BY A RUSH OF AIR, CABIN ALTITUDE ROSE TO 8,000 TO 9,000 FT. PERFORMED CABIN PRESSURIZATION LEAKAGE FUNCTIONAL TEST IAW 21-31-00-720-802. OPS CHECKED GOOD, NO DEFECTS NOTED. PERFORMED OPS CHECK OF EQUIPMENT RACK VENTILATION SYSTEM IAW 21-28-00 NO FAULTS NOTED. CHECKED NR 1 AND 2 AIR CONDITIONING CHECK VALVES IAW 21-20- 02 NO DEFECTS NOTED. AIR CONDITIONING DUCT AT RIGHT CENTER FUSELAGE WAS REPLACED DUE TO DAMAGE. THE CABIN PRESSURE CONTROLLER WAS REMOVED AND REPLACED AS PRECAUTIONARY.