A detonation flame arrestor including an outer cylinder, an inner cylinder, and fill media. The outer cylinder and inner cylinder are secured to a canister flange on one end and include a domed face (cap) on the other end. On assembly, the inner cylinder secured to the canister flange is positioned inside the outer cylinder secured to the canister flange, altogether forming a canister. The fill media is inserted in the canister between the inner cylinder and the outer cylinder. Both the outer cylinder and the inner cylinder include a tapered spiral wound wire screen which forms their respective cylindrical circumferences. Contaminates are constrained between adjacent windings of the tapered wire screen. The canister is positioned in an outer housing in the flow path of a gas pipeline in such a manner that a flame front traveling through the pipeline enters the outer housing, impinges upon the domed face of the outer cylinder, makes an abrupt turn to enter the canister, passes through the fill media where the flame is extinguished, and the gas flow makes a second abrupt turn to exit the canister and continue in the flow path of the pipeline. The fill media includes irregular shaped spheres which provide a large surface area which acts as a heat sink to extinguish the flame.