In my shower/tub combo, I sometimes accidentally plug the drain by bumping the attached drain cover with my foot, causing it to slightly turn and fall into plac

In my shower/tub combo, I sometimes accidentally plug the drain by bumping the attached drain cover with my foot, causing it to slightly turn and fall into place. This could easily happen if I fell. Sometimes I have a slow drain and I don't fix the until it becomes slow enough to fill up substantially during my shower. If I were unconscious in the sub with the shower running, it could have enough time to fill up. This would be especially true if my fall caused the water to switch to tub mode, which sends a lot more water into the tub. I had a friend in college who liked to take showers while pass-out drunk. He flooded the adjoining rooms several times when his unconscious body blocked the drain. Luckily this shower was not a tub or he may not have survived these incidents.