▁that ▁the ▁amount ▁of ▁radio active ▁waste ▁produced ▁should ▁be ▁hundreds ▁of ▁times ▁less ▁than ▁that ▁of ▁a ▁f ission ▁re actor , ▁and ▁that ▁it ▁should ▁produce ▁no ▁long - l ived ▁radio active ▁waste , ▁and ▁that ▁it ▁is ▁impossible ▁for ▁any ▁such ▁re actor ▁to ▁under go ▁a ▁large - scale ▁run away ▁chain ▁reaction . ▁A ▁direct ▁contact ▁of ▁the ▁pl asma ▁with ▁I TER ▁inner ▁walls ▁would ▁cont amin ate ▁it , ▁causing ▁it ▁to ▁cool ▁immediately ▁and ▁stop ▁the ▁fusion ▁process . ▁In ▁addition , ▁the ▁amount ▁of ▁fuel ▁contained ▁in ▁a ▁fusion ▁re actor ▁chamber ▁( one ▁half ▁gram ▁of ▁de uter ium / tr it ium ▁fuel ) ▁is ▁only ▁sufficient ▁to ▁sust ain ▁the ▁fusion ▁burn ▁pul se ▁from ▁minutes ▁up ▁to ▁an ▁hour ▁at ▁most , ▁whereas ▁a ▁f ission ▁re actor ▁usually ▁contains ▁several ▁years ' ▁worth ▁of ▁fuel . ▁Moreover , ▁some ▁det rit iation ▁systems ▁will ▁be ▁implemented , ▁so ▁that , ▁at ▁a ▁fuel ▁cycle ▁invent ory ▁level ▁of ▁about ▁, ▁I TER ▁will ▁eventually ▁need ▁to ▁rec ycle ▁large ▁amounts ▁of ▁tr it ium ▁and ▁at ▁turno vers ▁orders ▁of ▁magnitude ▁higher ▁than ▁any ▁preceding ▁tr it ium ▁facility ▁world wide . ▁ ▁In ▁the ▁case ▁of ▁an ▁accident ▁( or ▁sab ot age ), ▁it ▁is ▁expected ▁that ▁a ▁fusion ▁re actor ▁would ▁release ▁far ▁less ▁radio active ▁poll ution ▁than ▁would ▁an ▁ordinary ▁f ission ▁nuclear ▁station . ▁Furthermore , ▁I TER ' s ▁type ▁of