This is the sixth in a series on the Fukushima nuclear catastrophe based on the accounts of people who struggled to contain the crisis in its early stages. Job titles and ages are as of March 2011.

FUKUSHIMA — When the No. 1 reactor building exploded at the Fukushima No. 1 nuclear complex on March 12, 2011, blowing its concrete roof high into the sky, the employees were traumatized.