> Reaction times vary greatly with situation and from person to person between about 0.7 to 3 seconds (sec or s) or more. Some accident reconstruction specialists use 1.5 seconds. A controlled study in 2000 (IEA2000_ABS51.pdf) found average driver reaction brake time to be 2.3 seconds
Unless you expect rocket-propelled children being launched from the sidewalk, that's pretty much it.
(Of course the actual implementation within the entire system will be more complicated, but my point is - a computer can precisely compute what a human tends to intuit.)
A human can tell if there is something going on at the side of the road that might make the human jump into the road. Machines are nowhere near being able to understand the context of many situations that allow humans to predict these things.
How are you expecting to be able to regulate implementation specific details like this across the industry? How would you enforce entirely requirements like this? If it's left to invisible hand of the market I would assume that the demand would be higher for cars with more aggressive driving styles, that will get you from A to B faster.