In the third ring ("Thermal radiation radius"), my reading of it implies that you have 100% chance of third degree burns. But is that if you are standing outsid

In the third ring ("Thermal radiation radius"), my reading of it implies that you have 100% chance of third degree burns. But is that if you are standing outside in the street? I read recently that your chances of survival increase greatly if you stay inside your house with closed doors and windows. Or would the radiation still easily penetrate inside your house?