Inhibiting

                                       Checking or stopping the exothermic reaction of substances which contains oxygen within them is known as inhibiting. Certain materiel contain oxygen in themselves. Such materials when on fire cannot be extinguished by smothering as they release oxygen from them.Examples are , Gun powder, TNT and RD X etc. Such fires are due to self -sustaining ,continuous  heat producing (exothermic) chemical reactions.In such fires extinguishing is possible only by breaking the chemical chain reaction.This type of extinguishing is called Inhibiting.