▁itself ▁until ▁the ▁rate ▁of ▁comb ust ion ▁is ▁too ▁slow ▁to ▁maintain ▁the ▁chain ▁reaction . ▁ ▁In ▁contrast , ▁fire ▁is ▁intens ified ▁by ▁increasing ▁the ▁overall ▁rate ▁of ▁comb ust ion . ▁Method s ▁to ▁do ▁this ▁include ▁bal ancing ▁the ▁input ▁of ▁fuel ▁and ▁ox id izer ▁to ▁sto ichi ometric ▁proport ions , ▁increasing ▁fuel ▁and ▁ox id izer ▁input ▁in ▁this ▁bal anced ▁mix , ▁increasing ▁the ▁ambient ▁temperature ▁so ▁the ▁fire ' s ▁own ▁heat ▁is ▁better ▁able ▁to ▁sust ain ▁comb ust ion , ▁or ▁providing ▁a ▁catal yst , ▁a ▁non - react ant ▁medium ▁in ▁which ▁the ▁fuel ▁and ▁ox id izer ▁can ▁more ▁readily ▁react . ▁ ▁Fl ame ▁ ▁A ▁fl ame ▁is ▁a ▁mixture ▁of ▁react ing ▁g ases ▁and ▁sol ids ▁em itting ▁visible , ▁inf ra red , ▁and ▁sometimes ▁ult rav io let ▁light , ▁the ▁frequency ▁spectrum ▁of ▁which ▁depends ▁on ▁the ▁chemical ▁composition ▁of ▁the ▁burning ▁material ▁and ▁intermediate ▁reaction ▁products . ▁In ▁many ▁cases , ▁such ▁as ▁the ▁burning ▁of ▁organ ic ▁matter , ▁for ▁example ▁wood , ▁or ▁the ▁incomplete ▁comb ust ion ▁of ▁gas , ▁inc and es cent ▁solid ▁particles ▁called ▁so ot ▁produce ▁the ▁familiar ▁red - or ange ▁g low ▁of ▁" fire ". ▁This ▁light ▁has ▁a ▁continuous ▁spectrum . ▁Complete ▁comb ust ion ▁of ▁gas ▁has ▁a ▁dim ▁blue ▁color ▁due ▁to ▁the ▁emission ▁of ▁single - w avel ength ▁radiation ▁from ▁various ▁electron ▁trans itions ▁in