SPECIFIC PHENOMENA RELATING TO SEVERE ACCIDENTS

In the previous section reference is made to a number of specific phenom­ena that can directly influence the course of a severe accident. Rather than in­terrupt the discussion in that section of the effectiveness of the three containment barriers to cover these phenomena in detail, it was more conve­nient to deal with these topics in a separate section. Thus, this section covers

• fuel-coolant interactions—“steam explosions”

• debris beds and their cooling

• hydrogen formation—burning and explosions

• containment basemat melt-through and failure