They kind of fall in with the rules published by the FAA here, and previously were more or less a requirement to get a waiver before said rules. The whole worry

They kind of fall in with the rules published by the FAA here, and previously were more or less a requirement to get a waiver before said rules. The whole worry about flight over people is two-fold: 1. Props still spinning waiting to cut people up in event of flyaways or loss of power from one or more props 2. In the event of total loss of power, what is the total kinetic energy that would be imparted on an individual should the falling drone strike them Parachute systems effectively deal with both. A proper setup will power off the drone, making sure the props aren't spinning, and lower the rate of descent so minimal kinetic energy will be transferred in the event of a collision with a human being. The new rules firmly codify what requirements must be met to operate over people safely, and parachutes along with prop guards should easily meet them.