 Treatment of hazards. We have seen in the previous part how the internal failures are dealt with in the deterministic approach. Let's see now how we treat the hazards, internal or external hazards. Treatment of hazards is done through avoidance of the hazards. For instance, that could be done by sighting. If you want to avoid a flooding, you will set the platform at a level where the flooding could not reach the facility. Or by laying out the facility, for instance, in making geographical separation of redundant equipment. Or by probabilistic consideration. So that's the first way of treatment of hazards. There is a second way, if the hazard cannot be avoided, is to protect the safety function against the consequence of the hazards. And we will look at two examples. The first one is about fire. And again, you will see here how we used the defense in depth approach. The first level is through the prevention. So a way of preventing fire is to limit the amount of combustible materials. And for instance, and especially during the period where the reactor is shut down, where there is a lot of maintenance being done. It's important to organize a storage area in order to avoid accumulation of waste or any material that could be combustible. The second level is through monitoring. So each nuclear plant is equipped with a fire detection system with, of course, alarms. And the third level, to mitigate the consequence of fire, is first to install fire-resistant rooms in order if one fire spreading in a room, it will not propagate to another one. So that implies putting some fire doors or fire dampers on the ventilation system. And in addition, as a mitigation element, there are fire extinguishing systems, such as sprinkler or deluge. And the last line of mitigation is through the firefighting teams on each nuclear plant. There is permanently on call some fireman who are accustomed to intervene and to try to extinguish the fire. So we have seen an internal hazard, the fire. Let's look now at an external hazard, the plant crash. Through the statistics of the aeronautic industry, we can make a distinction between three kinds of flights. The commercial flights, the military flights and the general flights. The commercial flight, there are several hundreds of thousands of such flights per year. And the probability of accident per flight is in the order of 10 to the minus 6. Now if we combine that with the probability of the crash reaching per year a safety function with some conservative estimate, the result is in the order of 10 to the minus 8 per year and per safety function. So this figure is sufficiently low for the disregarding of this kind of accident. The military flight, the number is a little bit lower, but the probability of accident per flight is about 10 times more than for commercial flight. Therefore the probability of crashes of military aircraft is in the order of 10 to the minus 7. So in general, military flight crashes are not considered unless a nuclear plant is sighted not very far from a military airfield. And for instance in some countries and in some areas the nuclear plant is protected against military flight crash. But the general flights are in the order of several million a year. And the probability of accident per flight is also 10 times more than for the military. And so the approximate probability of during a crash reaching a safety function is in the order of 10 to the minus 6. So therefore the design of nuclear plants have to consider this kind of airplane crash. And there are two different planes considered as sort of reference. The Leedjet and the Cessna, one having its motor on the top. So let's see on this figure how the European pressurizer reactor is protected against a plant crash. So if you have a look from above you have here in the center the reactor building itself. And around here the four redundant trains of safety system and here the fuel building. And you have here the diesel generator which provides the powers to the plant if there is a loss of the electric grid. So you have on two of the safety system and on the reactor building and on the fuel building you have an aircraft shell which cover completely these equipments, these buildings and that are resistant to the crash of a plant. The two other trains here as well as diesel generator are separated geographically. So the probability of reaching by the same crash to two of them is very very low. And so this is a way, geographical separation is a way to protect the whole facility against this kind of events. And of course there is some auxiliary building or auxiliary facility without any safety role which are not protected. Thank you.