During the Fukushima Daiichi accident in 2011 the fuel rods underwent the degradation stages of a severe
accident, including the rapid oxidation of zirconium, which led on the one hand to the production of large quantities
of hydrogen, and on the other hand to additional heat production. Reducing the susceptibility of the cladding to the
high temperature oxidation in steam can improve greatly the accident tolerance of the cladding and thus help reduce
the risk of core meltdown. The worldwide research and development effort of the fuel nuclear industry to increase
fuel margins in severe accidents is referenced as the development of Enhanced Accident Tolerant Fuels (EATF).