Narrative:

We were proceeding westward at FL380. Approximately 100 mi east of the ZZZ1 VOR; the event occurred. At this time the crew experienced a pressure bump; and noticed a rapid rise in cabin pressure; followed by a 'cabin pressure' caution; and finally a red 'cabin altitude' warning. An emergency was declared and a lower altitude of X ft was requested and granted. Emergency descent memory items and checklists were performed while in the descent. After these tasks were completed the flight deck crew notified the flight attendants about the pressurization problem and asked about their condition and the condition of the passenger. The cabin crew indicated that all was well under the circumstances. The flight leveled out at X ft approximately 50 mi east of the ZZZ1 VOR. At that time; ATC asked if any assistance was required. We then called the cabin crew and requested a 'walk-through' to determine if any medical assistance would be required upon arrival at ZZZ2. The cabin crew called and stated that no medical attention was needed. With this information; ATC was notified that further assistance would not be needed. At this time the captain made a PA announcement explaining what had happened and why procedures were followed during the event. We reminded the passenger once again that medical assistance was available at ZZZ2 if needed. Also; during this time the first officer was contacting dispatch/maintenance and informing them of our condition and to update the X station of our status and have a passenger service representative there to meet us. The flight continued on to ZZZ2 and landed without incident. Supplemental information from acn 696488: at the gate at ZZZ2 we called maintenance. Safety valve #1 and valve #2 had flags showing failed open. Local maintenance deferred the pressurization system. We returned to ZZZ1 unpressurized with packs at 9000 ft.

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Original NASA ASRS Text

Title: CARJ FLT CREW MAKE AN EMER DSCNT FROM FL380 WHEN PRESSURIZATION SAFETY VALVES FAIL IN THE OPEN POS.

Narrative: WE WERE PROCEEDING WESTWARD AT FL380. APPROX 100 MI E OF THE ZZZ1 VOR; THE EVENT OCCURRED. AT THIS TIME THE CREW EXPERIENCED A PRESSURE BUMP; AND NOTICED A RAPID RISE IN CABIN PRESSURE; FOLLOWED BY A 'CABIN PRESSURE' CAUTION; AND FINALLY A RED 'CABIN ALT' WARNING. AN EMER WAS DECLARED AND A LOWER ALT OF X FT WAS REQUESTED AND GRANTED. EMER DSCNT MEMORY ITEMS AND CHKLISTS WERE PERFORMED WHILE IN THE DSCNT. AFTER THESE TASKS WERE COMPLETED THE FLT DECK CREW NOTIFIED THE FLT ATTENDANTS ABOUT THE PRESSURIZATION PROB AND ASKED ABOUT THEIR CONDITION AND THE CONDITION OF THE PAX. THE CABIN CREW INDICATED THAT ALL WAS WELL UNDER THE CIRCUMSTANCES. THE FLT LEVELED OUT AT X FT APPROX 50 MI E OF THE ZZZ1 VOR. AT THAT TIME; ATC ASKED IF ANY ASSISTANCE WAS REQUIRED. WE THEN CALLED THE CABIN CREW AND REQUESTED A 'WALK-THROUGH' TO DETERMINE IF ANY MEDICAL ASSISTANCE WOULD BE REQUIRED UPON ARR AT ZZZ2. THE CABIN CREW CALLED AND STATED THAT NO MEDICAL ATTN WAS NEEDED. WITH THIS INFO; ATC WAS NOTIFIED THAT FURTHER ASSISTANCE WOULD NOT BE NEEDED. AT THIS TIME THE CAPT MADE A PA ANNOUNCEMENT EXPLAINING WHAT HAD HAPPENED AND WHY PROCS WERE FOLLOWED DURING THE EVENT. WE REMINDED THE PAX ONCE AGAIN THAT MEDICAL ASSISTANCE WAS AVAILABLE AT ZZZ2 IF NEEDED. ALSO; DURING THIS TIME THE FO WAS CONTACTING DISPATCH/MAINT AND INFORMING THEM OF OUR CONDITION AND TO UPDATE THE X STATION OF OUR STATUS AND HAVE A PAX SVC REPRESENTATIVE THERE TO MEET US. THE FLT CONTINUED ON TO ZZZ2 AND LANDED WITHOUT INCIDENT. SUPPLEMENTAL INFO FROM ACN 696488: AT THE GATE AT ZZZ2 WE CALLED MAINT. SAFETY VALVE #1 AND VALVE #2 HAD FLAGS SHOWING FAILED OPEN. LCL MAINT DEFERRED THE PRESSURIZATION SYS. WE RETURNED TO ZZZ1 UNPRESSURIZED WITH PACKS AT 9000 FT.

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.