What was found
AIR CONDITIONING DIRTY SOCK SMELL BELOW 13000 ON DEPARTURE AND A RRIVAL NEED TO DF PACK 1 APPROVED FOR MEL 3152W CREW DID SAY THE SMELL WAS FROM PACK 1 COMPLYED WITH MEL 2152W . DUE TO PREVIOUS HISTORY NEED POSITIVE FIX, NOT JUST AN OPS CHECK *DM* UPDATED M/L WITH AIR RECIRCULATION HEPA FILTER 4012HM IN CASE NEEDED... ONLY SMELT IN COCKPIT, NO ODOR IN CABIN UNLOCKING FOR SIGN OFF ACP LEVEL ( A) DECONTAMINATION OF ENVIRONMENT CONTROL SYSTEM PER MM21-00-00-615-802-A USING APU AND ENGINE PNEUMATICS TO SUPPLY PACKS WITH VERY FAINT SMELL WHEN #1 PACK WAS RUNNING. REPLACED RECIRC FAN FILTERS PER MM21-21-41. ACP DECONTAMINATION OF ENVIRONMENT CONTROL SYSTEM AGAIN WITH NO SMELLS NOTED.