Narrative:

After leveloff at FL300 with all pressurization indications normal in the climb; I selected the pressure page on ECAM and noticed the cabin altitude at approximately 8000 ft and climbing rapidly. Asked for a lower altitude and began descending to 10000 ft. Advised ATC of our problem. During the descent; the cabin kept climbing. We donned the oxygen masks and initiated communications via interphone. The outflow valves indicated fully closed throughout the entire event. Ran the excessive cabin altitude checklist which did not alleviate the problem. Selected the other automatic pressure regulator -- no help. Attempted manual pressurization using checklist and the cabin continued to climb above 14500 ft which caused an oxygen mask deployment. Made the appropriate PA's to the passenger and to the crew to use the oxygen and return to seats until further notice. At no time did we receive ECAM alerts or warnings for cabin altitude. At the lower altitudes; the cabin began to descend to the aircraft altitude. Decision was made to return to ZZZ. Alerted dispatch via ACARS. Advised ZZZ approach of our situation as an emergency aircraft and landed overweight. Landing was smooth and touchdown was approximately 150 FPM. Upon arrival at gate; performed a postflt walkaround inspection and discovered 1 of 2 positive control area access doors and the check valve was broken off its hinges.

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Original NASA ASRS Text

Title: AN A300 FLT CREW REPORTS LOSS OF CABIN PRESSURE AT 30000 FT. THEY DECLARED AN EMERGENCY; DESCENDED; AND RETURNED TO DEPARTURE ARPT. FLT CREW REPORTS NO ECAM CABIN ALT ALERTS EVEN THOUGH THE CABIN ALT EXCEEDED 14500 FT.

Narrative: AFTER LEVELOFF AT FL300 WITH ALL PRESSURIZATION INDICATIONS NORMAL IN THE CLB; I SELECTED THE PRESSURE PAGE ON ECAM AND NOTICED THE CABIN ALT AT APPROX 8000 FT AND CLBING RAPIDLY. ASKED FOR A LOWER ALT AND BEGAN DSNDING TO 10000 FT. ADVISED ATC OF OUR PROB. DURING THE DSCNT; THE CABIN KEPT CLBING. WE DONNED THE OXYGEN MASKS AND INITIATED COMS VIA INTERPHONE. THE OUTFLOW VALVES INDICATED FULLY CLOSED THROUGHOUT THE ENTIRE EVENT. RAN THE EXCESSIVE CABIN ALT CHKLIST WHICH DID NOT ALLEVIATE THE PROB. SELECTED THE OTHER AUTO PRESSURE REGULATOR -- NO HELP. ATTEMPTED MANUAL PRESSURIZATION USING CHKLIST AND THE CABIN CONTINUED TO CLB ABOVE 14500 FT WHICH CAUSED AN OXYGEN MASK DEPLOYMENT. MADE THE APPROPRIATE PA'S TO THE PAX AND TO THE CREW TO USE THE OXYGEN AND RETURN TO SEATS UNTIL FURTHER NOTICE. AT NO TIME DID WE RECEIVE ECAM ALERTS OR WARNINGS FOR CABIN ALT. AT THE LOWER ALTS; THE CABIN BEGAN TO DSND TO THE ACFT ALT. DECISION WAS MADE TO RETURN TO ZZZ. ALERTED DISPATCH VIA ACARS. ADVISED ZZZ APCH OF OUR SITUATION AS AN EMER ACFT AND LANDED OVERWT. LNDG WAS SMOOTH AND TOUCHDOWN WAS APPROX 150 FPM. UPON ARR AT GATE; PERFORMED A POSTFLT WALKAROUND INSPECTION AND DISCOVERED 1 OF 2 PCA ACCESS DOORS AND THE CHK VALVE WAS BROKEN OFF ITS HINGES.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.