What's the "rule" in your house?

Speaking of interruptions, one of the realities of having kids at your feet in the kitchen is that they are a lot closer to the floor than you are.  And they put everything in their mouths.   Before I had kids, I would watch babies on the beach picking up whatever they could find and putting it in their mouths and I would wonder "how do those parents stand it?"  Three kids and one dog later...

We don't usually let him help with cleanup of faces, just floors and high chairs, but he does come in handy.  

Now, we keep our floors relatively clean, and the dog usually gets to anything we drop before a kid can, but the truth is that when I see my kids grab something off the floor, in the split-second before it gets to their mouth, my question has become "will that make them very sick?"  In other words, the "five second rule" has gone out the window.  It's really more of a "less than a minute" rule, but every now and then they'll find something that has been on the floor for who knows how long.  So I was very happy to see this justifying a "30-second rule."  But even better is this decision tree, created by two bloggers at SF Weekly.  What's the "rule" in your house?