Could someone more knowledgeable about nuclear physics than I am comment on the safety aspects of the positive void coefficient of the CANDU design? If the wate

Could someone more knowledgeable about nuclear physics than I am comment on the safety aspects of the positive void coefficient of the CANDU design? If the water boils, the reaction could run away. That said, the fact that a CANDU runs on unenriched natural uranium and the way it can be refuelled without shutting down power generation are seriously cool features. And they claim that the long time constant makes avoiding a Chernobyl-style excursion unlikely if the operators are awake. But I still worry about a design that isn't statically safe.