 the four processes involved in the flammability of materials are described and related to the various flame retardance mechanisms that may operate . following this 
 the four practical approaches used in improving flame retardance of materials are described . 
 each approach is illustrated with a number of typical examples of flame retardants or synthetic procedures used . 
 this overview of flammability , flame retardance , and flame retardants used is followed by a more detailed examination of most of the plastics manufactured in the united states during 1973 , their consumption patterns , and the primary types of flame retardants used in the flame retardance of the most used plastics . 
 the main types of flame retardants are illustrated with a number of typical commercial examples . 
 statistical data on flame retardant market size , flame retardant growth in plastics , and price ranges of common flame retardants are presented.imagesfigure 1.figure 2.figure 3.figure 4 . 
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