retardant foam and the flame retardant tube comprise graphite aluminum hydroxide and ammonium phosphate in addition to a base resin the flame blocking system prevents flames and toxic gases generated during a fire or a similar accident from being spread through holes through which a wire a cable or a pipe is installed across a wall of buildings or ships which can reduce damage to life and property application_number US 83885810 A description with reference to fig1 to 3 various cables wires and pipes etc pass through an open hole 20 formed in a partition wall of for example a building or ship the flame blocking system is installed in the open hole 20 and generally includes flame retardant foam 30 and a flame retardant tube 40 in the state that the flame retardant foam 30 is cut to have a size suitable for the open hole 20 and fills the open hole 20 at least one flame retardant tube 40 is inserted into the flame retardant foam 30 various cables wires and pipes etc 50 which are connected with one another through a partition wall 10 in a building are positioned in the flame retardant tube 40 in other words the flame retardant tube 40 encircles surrounds or covers a portion of the cable etc and is inserted into the flame retardant foam 30 the partition wall 10 may be for example a cement or brick partition wall for a general building or a steel plate partition wall for an interior structure of a ship thus the partition wall 10 of the present invention is not limited to particular materials in addition the open hole 20 defines a hole in the partition wall 10 through which various cables and wires etc pass the hole may have diverse sizes and.