What was found
FUME EVENT DESCENDING THROUGH 4,000FT THRUST WAS AT IDLE BEING BROUGHT UP. ISOLATED PACK 1, FUMES DISSAPARTED WITHIN A FEW MINUTES, FUMES WERE ALSO NOTICED BY F/A'S BOTH REAR & FORWARD AND THROUGHOUT ENTIRE CABIN-PERFORMED TSM 05-50-00-810-831-A PERFORMED DECOMANINATION OF THE EC-8 SYSTEM IAW AMM 21-00-00. NO FUMES NOTED. R/R RECITCULATION FILTERS IAW AMM 21-21-02. A/C OKAY FOR SVC