What was found
THE CREW REPORTED THAT AFTER ICE TEST, AND ONCE PACKS WERE SELECTED ON THEY HAD NOTICEABLE SMOKE AND PARTICLES STATING TO FLOOD THE COCKPIT. BOTH PACK AND BLEED 1 WERE SHUTOFF TO CONTINUE THE FLIGHT. THE ACFT LANDED IN WITHOUT INCIDENT WHERE MAINTENANCE INSPECTED THE ACFT AND PLACED PACK 1 ON MEL 21-51-00-3, AND THE ACFT WAS APPROVED FOR RETURN TO SERVICE. R & R THE NR 1 ACM, OPERATIONALLY TESTED WITH NO DEFECTS NOTED, REMOVED THE MEL, AND THE ACFT WAS APPROVED FOR RETURN TO SERVICE.