I love this reply. We can go even further. If we would approach air safety in such way as Nuclear, then de Havilland DH.106 Comet would be first and last commercial jet.

Nuclear fision reactors safety technology have moved further. There are challenges, but we havent even tried to solve them fully (as we were busy improving gas burning efficiency)

> No remotely modern reactor has melted down

TMI and Fukushima were both "modern" when built. All reactors that melted down did because operators ignored construction, maintenance, or operating safety standards. Other plants not yet melted down show evidence of more construction standard failings: pumps installed despite failing to meet specifications, bolts of substituted, inadequate steel. Diablo Canyon is built directly on a fault line. Now we learn that new EPR plants are inherently flawed, by design.

Ignoring standards is, by the evidence, itself standard procedure for building and operating civil nuke plants. Our global society, as it is conducted, is by the evidence unable to produce and operate a safe civil nuke.

What are the biggest safety improvements that have become mainstream since Chernobyl?

The improvements were already mainstream before Chernobyl was built. It's all about making reactors tolerant to operator error, and if something does go wrong, make sure it goes wrong slowly, so operators have lots of time to react.

The RBMK reactor is quite an elegant design. Simple plug-and-play architecture for adding and removing fuel and other assemblies while the reactor was running, perfect for things like doping silicon for semiconductors and producing plutonium for weapons. But to get this capability you have to either give up affordability or safety, and they chose to give up safety.

The most obvious is that rods naturally fall into water now, which dampens the neutron exchange to a stop, which works automatically in case of power cut (The rest of improvements are about preventing water from overheating and forming H2, and preventing H2 from overpressuring the chambers or exploding, which happened in both Chernobyl and Fukushima).

Control rods aren't tipped with iron. Iron has a positive coefficient of reactivity.

That's a great analogy.