B737 FLC NEGLECTS TO RESET ALTIMETER PASSING 18000 FT.

Narrative

THE FLT DEPARTED CLE WITH AN ALTIMETER OF 30.30. PASSING 18000 FT WHERE A STANDARD CALLOUT OF 29.92 IS MADE; THERE WAS NO CALLOUT BY THE FO. THE 'B' FLT ATTENDANT CAME UP TO THE COCKPIT TO RPT A PAX PROB AS WE PASSED 18000 FT. BEING PREOCCUPIED WITH THE CONVERSATION WE BOTH NEGLECTED TO RESET OUR ALTIMETERS TO 29.92. OF COURSE WE WERE ALMOST 400 FT OFF. THE CTLR QUERIED US ABOUT OUR ALT AND WE REALIZED WE WERE OFF. HE THEN GAVE US A XING RESTR AND THE OVERSIGHT WAS CORRECTED. WE HAD NO TFC CONFLICTS; BUT WE REALIZED THE OVERSIGHT. WE LANDED AT PHL UNEVENTFULLY. OUR PREOCCUPATION WITH THE FLT ATTENDANT CONVERSATION DURING OUR CLB THROUGH 18000 FT CAUSED THIS OVERSIGHT; BUT BECAUSE THIS IS A STANDARD CALLOUT WE SHOULD HAVE CORRECTED IT SOONER. THE FLT ATTENDANT WAS ONLY IN THE COCKPIT FOR APPROX 1 MIN. THIS WAS THE 3RD LEG OF A 4 LEG DAY AND WE BOTH WERE A LITTLE TIRED FROM THE PREVIOUS NIGHT'S SHORT OVERNIGHT. SETTING 29.92 IS SUCH A ROUTINE MATTER THAT OVERSIGHTS ARE BOUND TO OCCUR. MAYBE AN ALT ALERTER THROUGH 18000 FT WOULD BE A GOOD IDEA. ONCE AGAIN THE HUMAN FACTORS ARE INVOLVED. THE FO AND I DECIDED UPON ARR IN PHL THAT WE WOULD BOTH SUBMIT NASA RPTS EVEN THOUGH THE CTLR DIDN'T SEEM CONCERNED. THE FO WAS A BOTTOM RESERVE PLT AND HASN'T FLOWN VERY MUCH. HE WAS RUSTY IN MANY AREAS SIMPLY BECAUSE HE DOESN'T FLY VERY OFTEN. 3 FLT ATTENDANTS; 2 CREW. IT'S STILL MY RESPONSIBILITY TO XCHK AND WE BOTH MISSED THE CALLOUT.