ACR FLC FORGETS TO RESET ALTIMETER AT FL180.

Narrative

DURING CLB THROUGH FL180 NEITHER PLT REMEMBERED TO CHANGE ALTIMETER SETTING TO 29.92 IN. THE DEP ALTIMETER OF 30.32 WAS STILL SET AT LEVEL OFF AT FL310. THE ERROR WAS DISCOVERED WHEN THE CAPT NOTED THE TCASII SHOWING OTHER TFC APPROX +/- 300 FT FROM OUT ALT OR +/- 300 FT FROM MULTIPLES OF 1000 FT FROM OUT ALT. WE RESET 29.92 AND CLBED TO THE PROPER ALT IMMEDIATELY. WE KNOW OF NO CONFLICT THAT AROSE AND CTR MADE NO MENTION OF THE DEV. THIS SITUATION OCCURRED BECAUSE BOTH OF US WERE DISTR BY OTHER TASKS (SIMULTANEOUS RADIO CALLS: ONE TO THE COMPANY TO MAKE SURE THEY HAD OUR TKOF TIME; THE OTHER TO ARTCC WITH A NEW CLRNC) AS WE CLBED THROUGH FL180 WHERE THE ALTIMETER SHOULD HAVE BEEN RESET. WHEN WE FINISHED THE OTHER TASKS NEITHER OF US REMEMBERED TO GO BACK AND REDO THE CHKLIST. (MY PRIMARY RESPONSIBILITY AS PNF). PREVENTION: DON'T INITIATE EXTRANEOUS TASKS AT A CRITICAL PHASE OF FLT. RECOGNIZE DISTRS WHEN THEY OCCUR AND GO BACK AND REACCOMPLISH CHKLIST. BUILD A HABIT PATTERN OF CHKING FOR PROPER ALTIMETER SETTING AT 'ONE THOUSAND PRIOR' CALL.