Not a commercial reactor but US lost 3 people trying to hand operate a small reactor with minimal safety: https://en.wikipedia.org/wiki/SL-1
“On Tuesday, January 3, 1961, SL-1 was being prepared for restart after a shutdown of 11 days over the holidays. Maintenance procedures required that rods be manually withdrawn a few inches to reconnect each one to its drive mechanism. At 9:01 pm MST, Rod 9 was suddenly withdrawn too far, causing SL-1 to go prompt critical instantly. In four milliseconds, the heat generated by the resulting enormous power excursion caused fuel inside the core to melt and to explosively vaporize.”
The industry didn’t just randomly get so risk averse there where a lot of meltdowns and other issues over time.
Not a commercial reactor but US lost 3 people trying to hand operate a small reactor with minimal safety: https://en.wikipedia.org/wiki/SL-1
“On Tuesday, January 3, 1961, SL-1 was being prepared for restart after a shutdown of 11 days over the holidays. Maintenance procedures required that rods be manually withdrawn a few inches to reconnect each one to its drive mechanism. At 9:01 pm MST, Rod 9 was suddenly withdrawn too far, causing SL-1 to go prompt critical instantly. In four milliseconds, the heat generated by the resulting enormous power excursion caused fuel inside the core to melt and to explosively vaporize.”
The industry didn’t just randomly get so risk averse there where a lot of meltdowns and other issues over time.