by Katherine Berezowskyj
Yes, Three Mile Island and Chernobyl were accidents, but they were also lessons that strengthened safety mentality. These lessons ushered a new level of safety, observation, and prevention. There is no “propensity to underestimate the chances of ‘low probability, high cost events’,” in the nuclear industry, as the nuclear industry knows that no risk is acceptable.
Safety is not only a question of regulations and procedures. Safety is part of the nuclear industry’s fabric. It is part of the mindset and culture. That is why it can always be improved. It is fair to recognize that safety improvements are regularly implemented, at both design and operational levels, especially over the 30 year span since Three Mile Island.
The latest generation of reactors marries this mentality and decades of improvements. AREVA’s EPR reactor design has advanced safety features, providing even greater provisions for the risks arising from internal and external hazards. The reactor is both a reinforced steel and concrete box: whatever happens outside, no impact inside; whatever happens inside, no impact outside. The accident consequences are limited by an optimal combination of passive and active safety systems.
The EPR reactor is designed to resist an airplane crash with a double containment shell. There is a quadruple redundancy with independent trains for each safeguard system, core melt catcher and an even lower probability of core damage.
But let’s not forget that the independent regulatory for the industry, the U. S. Nuclear Regulator Commission (NRC). Every nuclear power plant in the United States receives more than 2,000 hours of inspection and oversight activity each year from the NRC, in addition to a minimum of two resident inspectors on site at every plant every day of the year.
The nuclear industry is thinking of the risks both big and small and is working to prevent risks that don’t yet exist. Because no risk is acceptable.