Narrative:

I was flying purser. On the 2ND leg of the trip upon completion of my safety checks; I was met by a mechanic who informed me upon entering the aircraft that morning to open the door 1L from the night before; he had gone down below the aircraft to verify that door 1L was disarmed by looking directly up from below. Upon doing this safety check he noticed door 1L girt bar was engaged on one side. He entered through the back entrance and in fact it was armed. He disarmed the door 1L from the inside of the cabin. Upon questioning the mechanic he stated the aircraft had come in from the night before from ZZZ. He also stated his trainer had always taught him to verify the B737 door 1L disarmed by going underneath the aircraft. I feel this safety check was vital in not having a blown slide. Perhaps when the door was shut after the crew deplaned the night before by the customer service agent the door might have fallen out of the safety brackets and rearmed it on the one side.

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Original NASA ASRS Text

Title: A B737-300 CABIN ATTENDANT COMMENTS THAT A MECH VERIFIED HER ACT'S 1L SLIDE WAS ARMED BY VIEWING THE GIRT BAR FROM OUTSIDE BENEATH THE DOOR.

Narrative: I WAS FLYING PURSER. ON THE 2ND LEG OF THE TRIP UPON COMPLETION OF MY SAFETY CHKS; I WAS MET BY A MECH WHO INFORMED ME UPON ENTERING THE ACFT THAT MORNING TO OPEN THE DOOR 1L FROM THE NIGHT BEFORE; HE HAD GONE DOWN BELOW THE ACFT TO VERIFY THAT DOOR 1L WAS DISARMED BY LOOKING DIRECTLY UP FROM BELOW. UPON DOING THIS SAFETY CHK HE NOTICED DOOR 1L GIRT BAR WAS ENGAGED ON ONE SIDE. HE ENTERED THROUGH THE BACK ENTRANCE AND IN FACT IT WAS ARMED. HE DISARMED THE DOOR 1L FROM THE INSIDE OF THE CABIN. UPON QUESTIONING THE MECH HE STATED THE ACFT HAD COME IN FROM THE NIGHT BEFORE FROM ZZZ. HE ALSO STATED HIS TRAINER HAD ALWAYS TAUGHT HIM TO VERIFY THE B737 DOOR 1L DISARMED BY GOING UNDERNEATH THE ACFT. I FEEL THIS SAFETY CHK WAS VITAL IN NOT HAVING A BLOWN SLIDE. PERHAPS WHEN THE DOOR WAS SHUT AFTER THE CREW DEPLANED THE NIGHT BEFORE BY THE CUSTOMER SVC AGENT THE DOOR MIGHT HAVE FALLEN OUT OF THE SAFETY BRACKETS AND REARMED IT ON THE ONE SIDE.

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.