For purposes of this chapter, the following terms have the following meanings:
(a) “Catastrophe” means a natural or man-made event that causes a vacancy in at least 101 of the offices of the United States House of Representatives, including at least one of the offices representing California, or at least one-fourth of the total number of offices representing California.
(b) “Vacancy” means the death or disappearance, as a result of a catastrophe, of a Representative in Congress.
(c) “Disappearance” means the inability to establish conclusively whether a Representative in Congress has survived a catastrophe.