MD80 EVACED ON TXWY DUE TO CABIN SMOKE.

Narrative

AFTER NORMAL LNDG AND TAXIING CLR OF RWY; APU WAS STARTED DUE TO 10-15 MIN GATE HOLD. WHILE TAXIING AND BEFORE CONTACT WITH GND CTL; A SMOKEY ODOR WAS DETECTED IN COCKPIT BY BOTH PLTS. WE AT FIRST THOUGHT IT WAS COMING FROM OUTSIDE; AS IT WAS VERY FAINT AND WE HEARD NOTHING FROM FLT ATTENDANTS. THE ODOR PERSISTED AND I THOUGHT IT SMELLED ELECTRICAL IN NATURE AS IT INCREASED. FLT ATTENDANTS WERE CALLED AT THAT TIME TO INQUIRE IF THEY WERE EXPERIENCING SAME ODORS IN CABIN. #1 FLT ATTENDANT SAID HE SMELLED A FAINT ODOR AS WELL. AT THIS POINT #2 FLT ATTENDANT CAME ON INTERPHONE AND EXCITEDLY POINTED OUT SHE COULD SEE SMOKE COMING FROM BEHIND THE CAPT NEAR THE FORWARD JUMPSEAT. SHORTLY THEREAFTER; SHE SAID THE SMOKE WAS NOW COMING FROM THE MID CABIN AREA AND WE NEEDED TO STOP THE ACFT AND CONSIDER EVAC. I COORD WITH GND TO PULL OUT OF THE WAY ON TXWY DUE TO SMOKE IN THE CABIN AND REQUESTED CFR EQUIP BE DISPATCHED; THUS DECLARING THE SITUATION AN EMER. I MADE A PA TO THE PAX ASKING THEM TO STAY CALM AS WE WERE TRYING TO FIND THE SOURCE OF THE SMOKE WHILE COORD AN EXPEDITIOUS EGRESS OF THE ACFT. I OPENED THE COCKPIT DOOR TO ALSO ASSESS THE SITUATION AND SAW THAT MANY PAX WERE ALREADY OUT OF THEIR SEATS. AT THIS POINT; I KNEW IT WAS FUTILE TO TRY AND RUN CHKLISTS TO DISSIPATE THE SMOKE AND ELECTED TO SIMPLY SHUT DOWN THE ENGS AND PACKS AND RUN THE EMER EVAC CHKLIST. WE WERE UNABLE TO COMPLETE THE CHKLIST BEFORE THE EVAC WAS STARTED BY THE FLT ATTENDANTS. THEY ELECTED WISELY TO USE THE TAIL CONE EXIT AND THE EVAC WAS BOTH EXPEDITIOUSLY AND SAFELY CONDUCTED. THERE WERE NO INJURIES TO PAX OR CREW. WITH THE ACFT SHUT DOWN AND DOORS OPEN; THE SMOKE QUICKLY CLRED. I STAYED ON BOARD TO ASSIST EMER PERSONNEL IN CHKING THE AREAS WHERE SMOKE WAS RPTED. NO HOT SPOTS WERE FOUND.