Next to safe rooms and storm shelters, a basement is best. Otherwise choose ground floor center rooms surrounded by other rooms. If no interior rooms are available, choose rooms on the north and east sides of your shelter. Stay near the innermost walls and avoid rooms on the south and west because tornados usually travel from southwest to northeast. Choose a small closet or bathroom.
Small rooms are less susceptible to collapse.
Take shelter in the bathtub if there are no glass tub enclosures or large mirrors nearby. Avoid gymnasiums and auditoriums. In shopping centers or malls seek the smaller interior shops on the ground floor. Avoid large open rooms as well as the south and west walls. Evacuate mobile homes and vehicles, seeking structure in a substantial structure, ditch or culvert.