The invention provides a chimney fire access device for injecting a fire extinguishing compound into the interior of an elongate vertical chimney stack, the stack having: a side wall and a longitudinal axis, the device comprising: a tube extending transversely through the stack side wall, the tube having an input end, a midportion and an output end; mounting means for mounting the tube to the stack side wall; nozzle means disposed on the output end of the tube for spraying a fire extinguishing compound in an upstream direction; trap means disposed within the midportion of the tube for impeding backflow of solid particles from the interior of the stack through the side wall; and fire extinguishing compound injection means disposed on the input end of the tube for conveying compound from a source of extinguishing compound.