If 90 and in old folks home, why bother with going to bath tub if tornado?

Only U can answer. If you believe you have had a good life & are ready to throw caution to the wind, it's your choice. The tub might not do the trick anyway. You might want to consider the bizarre things that happen with tornadoes. If you plan to eventually rest in "one" piece, the tub might be a good idea.