What was found
DURING PREFLIGHT, RAMP CREW STARTED DE-ICING AIRCRAFT WITHOUT OUR KNOWLEDGE NOR WITH AIRCRAFT CONFIGURED FOR DE-ICING. RECEIVED LAV SMOKE WARNING FOLLOWED QUICKLY BY FUMES & SMOKE LIKE SUBSTANCE THROUGHOUT ENTIRE CABIN. APU BLEED WAS ON, PACKS ON DESPITE IMMEDIATELY TURNING OFF BLEED AND PACKS. FUMES BECAME VERY STRONG AND LONG LASTING. PERFORM LEVEL B ECS DECONTAMINATION IAW AMM 21-00-00-616- 803A. NO RESIDUAL ODOR NOTED. R & R LT & RT RECIRCULATION FILTERS IAW AMM 21-21. NO ODOR DETECTION IN CABIN. AC OK FOR SERVICE. (LP: 7336882)