Narrative:

Upon shutdown of aircraft engines at dca; the caution message 'altitude limiter' was displayed. Maintenance was called by the captain and I reviewed MEL 21-27 and 21-28 while waiting for maintenance to come to the aircraft. While the captain and mechanic discussed the issue and wrote it up in the maintenance log; I was in the galley area and first few rows of the cabin listening to the discussion. After completion of the procedure by maintenance; we boarded 8 passenger; ran the checklist and I observed the placard on the pressurization panel. I assumed that the MEL procedure had been accomplished while I was out of the cockpit and during my preflight. Callback conversation with reporter revealed the following information: the cabin pressure limiter function of the cabin pressurization system was inoperative and deferred per the MEL. The flight was to be made unpressurized but at 10000 ft it was noted the cabin was pressurized. Maintenance failed to complete the special procedure of the MEL by not activating the emergency depressurization switch.

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Original NASA ASRS Text

Title: A CRJ700 HAD THE ALT LIMITER DEFERRED PER THE MEL. FLT TO BE MADE UNPRESSURIZED. AT 10000 FT FLT CREW NOTED CABIN WAS PRESSURIZED.

Narrative: UPON SHUTDOWN OF ACFT ENGS AT DCA; THE CAUTION MESSAGE 'ALT LIMITER' WAS DISPLAYED. MAINT WAS CALLED BY THE CAPT AND I REVIEWED MEL 21-27 AND 21-28 WHILE WAITING FOR MAINT TO COME TO THE ACFT. WHILE THE CAPT AND MECH DISCUSSED THE ISSUE AND WROTE IT UP IN THE MAINT LOG; I WAS IN THE GALLEY AREA AND FIRST FEW ROWS OF THE CABIN LISTENING TO THE DISCUSSION. AFTER COMPLETION OF THE PROC BY MAINT; WE BOARDED 8 PAX; RAN THE CHKLIST AND I OBSERVED THE PLACARD ON THE PRESSURIZATION PANEL. I ASSUMED THAT THE MEL PROC HAD BEEN ACCOMPLISHED WHILE I WAS OUT OF THE COCKPIT AND DURING MY PREFLT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CABIN PRESSURE LIMITER FUNCTION OF THE CABIN PRESSURIZATION SYS WAS INOP AND DEFERRED PER THE MEL. THE FLT WAS TO BE MADE UNPRESSURIZED BUT AT 10000 FT IT WAS NOTED THE CABIN WAS PRESSURIZED. MAINT FAILED TO COMPLETE THE SPECIAL PROC OF THE MEL BY NOT ACTIVATING THE EMER DEPRESSURIZATION SWITCH.

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.