Following the 2011 Fukushima accident, there has been considerable interest in safer cladding materials. During the accident, at elevated temperatures the Zircaloy cladding reacted with steam to produce hydrogen gas:
This hydrogen accumulated and caused explosions at the reactor plant. As a result, accident-tolerant fuel (ATF) programmes are now investigating alternative cladding materials such as silicon carbide (SiC) and FeCrAl alloys that do not generate hydrogen under accident conditions.