AbstractCommercial acrylonitrile butadiene styrene (ABS) polymers are among the most flammable of the currently available range of thermoplastic materials. In addition to having a rather low limiting oxygen index (LOI) value in the range 18.3–18.8, ABS polymers also produce compious amounts of smoke and hazardous gases when burnign in the air. In a recent study directed towards preparing and evaluating compounds which would simultaneously reduce the flammability and smoke produced from burning thermoplastic polymers, a synergistic flame‐retarding/smoke‐suppressing system based on organoiron compounds has been produced, which when properly compounded into ABS/PVC [poly(vinyl chloride)] blends more than doubles the LOI nad at the same time reduces smoke production signific