As in any book, we have to explore
the beginning of this nuclear philosophy.
And to do it, we can see 4 different concepts
that are the bases for this philosophy.
All these four concepts are linked to the history
that we saw in the first Nooc,
when we defined the different ages of technology.
Or the different ages of safety.
So, first, the foundations of the nuclear safety started
with a very simple principle, the determinism.
Basically, every outcome has a cause
and that cause can be explained
And by explaining that cause, you can explain what happened.
As I have said before, this came from the Age of Technology,
when the machines were the only source
of negative outcomes, or errors or accidents.
Machines were very simple,
and they could be decomposed in the different parts.
The way they worked could be understood perfectly.
Every outcome has an explanation for it,
and could be traced back to the source of the error.
This leads to the next part of the philosophy.
That is once again, as we said previously,
that systems were considered deterministic.
So, we enter in the era of mechanistic thinking.
Everything could be explained, and every system could be decomposed
to their minimum parts.
The nuclear industry was born during the Age of Technology,
so, the only considerations for safety were for example,
that the machines could be explained as the sum of different parts,
That means, as I have said three times now,
they can be decomposed.
Also, as we said in the first statement,
the basis of nuclear safety worked in a deterministic way.
The outcomes are predictable in machines.
This means that every negative outcome,
let say an accident or an incident,
in machines can be understood by understanding
how their different parts work.
And then, they can be explained.
The final statement says that every machine can be analyzed.
So, the outcome can be understood.
Then, the Safety Analysis would let us know
how safe a machine is.
And thus, we would be able to anticipate any dangerous event.
So, this is the beginning of the nuclear safety.
It has its roots in all the safety developments made
before Three Mile Island.
And after that, it was discovered
that humans can provoke
different challenges due to their actions.
So they have to be taken into account.
Specially training and to develop a strong safety culture,
in order to prevent all those negative outcomes.
But, before evolving the safety culture, we have to see other concepts.
So now, let's continue with the definition of risk,
that we already saw, but we are going to expand it now.