[Coda]

As mentioned earlier, the door frame thing is obsolete advice. It was valid for houses built before modern building codes because door frames were reinforced by virtue of having to have a door put into them. Anything built since, like, the 1960s is constructed in a more earthquake-resistant fashion, and you're in more danger from stuff on the walls falling down (or from YOU falling down) than you are from the walls themselves falling down, so you're better off taking cover under a heavy piece of furniture that will block the debris.