After these deterministic analyses were made,
the following risk areas were established,
giving rise to what we call "The Deterministic Evolve".
In the deterministic evolve we will have
what we call "Acceptable Area of Operation."
That will go from normal operation to transients, to accidents,
to severe accidents.
As we can see, normal operation will include those events
that have high probability, or are more likely,
but less severity.
Also, we have that severe accidents
are really severe events, but with a very low probability,
less than one in a million.
As it was not possible to study all the risk-probability pairs,
we choose what we call "Design Basis Accident"
on each area and they were establishing
the table that we are going to see now.
Here we have two different event classifications.
The first one, or four, but we have the NRC definition,
that in the 10CFR50 does not limit the frequency of events
in practice, when selecting the Design Basic Accident.
So there are many accidents of lower frequency
that are left out.
And we can see that there we have normal operation
and normal operation and accidents.
Also, we have de ANS51.1 of 1983,
which is more explicit in excluding events
with expected frequencies below one million, one in one million.
And there we will see that we evolve from Condition 1, 2, 3, and 4
to more categories.
And finally, we have the event classification
in operational transients.
Fuel failure should not occur. That means that when we apply
the simulation models of the safety analysis,
conditions will not be reached
in which the fuel rods can fail.
In this case, or in the case of pressure barrier
of the reactor coolant, a 110% of the operational pressure
cannot be exceeded,
and therefore, there can be no releases of radioactive materials.
In accidents, limited damage to fuel can happen or occur,
but it should maintain its geometry.
And those are the different explanations
for the Deterministic Evolve.