The tsunami that followed the Tōhoku earthquake overtopped the plant's seawall and flooded emergency diesel generators located in basements, causing a station blackout. Without cooling, three reactor cores melted down and hydrogen explosions damaged containment buildings.
Radiation exposure has been officially linked to one worker death. However, roughly 2,300 deaths in Fukushima Prefecture have been attributed to the stress and disruption of prolonged evacuation, particularly among elderly and hospitalised people — a widely studied example of how evacuation itself carries risk.
The accident led Japan to shut down its nuclear fleet for review and prompted worldwide reassessment of backup power protection, flood defences and multi-hazard planning at nuclear sites.
Why this event still matters
Historical incidents shape the rules that protect people today — building codes, evacuation policy, warning systems and inspection regimes almost always trace back to a specific disaster. Studying Fukushima Daiichi Nuclear Accident alongside current events is how preparedness improves.
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