“Nuclear power is unsafe because it’s so safe”. Wait… what?!

Well, the safety thing comes down to redundancy, and the fact of the matter is that you could make the argument that a modern reactor has more safety features than it really needs to. That said, it is always good to air on the side of safety, and since the operating costs are low in general, it doesn’t ad that much cost to make it ultra-safe.

A modern power reactor has a very well built containment structure that will hold against tornado or the explosion of the pressure vessel at full power or a plane crashing into it. Have we ever needed the containment structure to contain a catastrophic failure of the pressure vessel? No. But it’s still nice to have it there, because most nuclear supporters are all about safety so we like having extra layers that we know we’ll almost certainly never need.

It’s like the railing on the staircase. Lets say you have a staircase that only goes up one story and is fairly wide and not very steep. Do you really need a railing? Well, if the railing was not there, it’s still unlikely that you’d fall off and even if you did fall off, you probably wouldn’t be that badly hurt, especially if you were not all the way up the stairs.

I’d have no problem climbing a one story staircase without a railing, but I still think it’s a good idea to have one, just to make it even safer, despite the fact that it’s not that unsafe even with one.

Another thing to consider about this is that a lot of the extreme safety measures come down to addressing public and political concerns. One of the things about nuclear power is that you have to avoid any kind of accident, even if it’s not fatal. In the US we had the Three Mile Island incident which didn’t hurt anyone. All the active safety systems failed and the core ended up partially melting. The damage was all internal, but the reactor was a write-off.

In another industry you’d look at such an event and say that it was regrettable and expensive, but it’s not a huge deal that the systems fail and equipment gets destroyed. Sure, when it happens, it’s a loss, but you have insurance and so it’s an acceptable risk. The problem is that with the nuclear incident, it’s not simply an equipment write-off, it’s a PR disaster that impacts decades later.

You see this same kind of redundant safety consideration elsewhere.

A modern aircraft is piloted by someone who has simulator trained for all kinds of incidents they’ll almost certainly never face. An airline pilot will train repeatedly to bring an aircraft down safely with no engines or in extreme windshere or any number of other events that almost never happen. It has redundant backup hydraulics and it has multiple emergency exits, flotation seat cushions, life vests, oxygen masks, inflatable slides that double as life rafts, med kits, locator beacons for the rafts.

Many of the scenarios that have been trained for and equipped for have never even happened in reality. I’m not aware of any situation where an aircraft has been forced to ditch in the open ocean during a storm and then have the passengers all survive on the life rafts, using the supplies on them, for a period of days, while receiving first aid until finally a search and rescue aircraft is signaled with a mirror or flair. Despite that, should that event happen, the crew is trained for it and there is equipment for it.