Several measures are taken during the fuel loading process to ensure there will be no need to re-open a welded canister. It is filled with an ‘inert gas’ (such as Helium), i.e. a gas that does not chemically react and that prevents any corrosion. Each canister is also leak-tested prior to use to ensure the inert environment will remain inside the canister. The inert environment prevents the stored spent fuel from degrading and eliminates the need to inspect the fuel or the interior of the canister.
