Narrative:

Return to gate with maintenance problem. I wrote up maintenance problem in logbook (pressurization problem) and left aircraft to go to restroom. When I returned, mechanic was in cockpit doing engine run (passenger still on board). Not a good idea. If emergency evacuate/evacuation required, mechanic not trained to evacuate/evacuation passenger. I discussed problem with maintenance supervisor.

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Original NASA ASRS Text

Title: AFTER RETURN TO GATE, MECH STARTED ENG WITH PAX ABOARD AND CAPT NOT IN COCKPIT.

Narrative: RETURN TO GATE WITH MAINT PROB. I WROTE UP MAINT PROB IN LOGBOOK (PRESSURIZATION PROB) AND LEFT ACFT TO GO TO RESTROOM. WHEN I RETURNED, MECH WAS IN COCKPIT DOING ENG RUN (PAX STILL ON BOARD). NOT A GOOD IDEA. IF EMER EVAC REQUIRED, MECH NOT TRAINED TO EVAC PAX. I DISCUSSED PROB WITH MAINT SUPVR.

Data retrieved from NASA's ASRS site as of July 2007 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.