Are All Main Drains Created Equal?

[JohnT]

Interesting. So then e.g., you could dive down to your drain and feel water circulation?

So if there's circulation there, in other pools, that means the cover is off? Why doesn't it suck people to it? In this commercial kiddie pool where the girl was almost fatally injured (and whose life is forever altered) why would the drain be closed in the first place if its function is to add to the circulation of water?

Sorry for all the questions, John, but still confused.

You can't feel the suction. All main drains are supposed to have a cover on them, but the water flows through the cover. A common design for the cover is a raised flat surface with the openings around the edge. It looks solid from above. Go to this link for drain info and pictures: http://www.drainsafe.com/print_summary.htm