I'm honestly surprised this doesn't happen more often. I used to go to Texas and Nashville IndyCar races, as well as Iowa once. Those cars are running at speed to get back around to the back of the pack. I've seen some pretty close calls with both emergency vehicles, as well as other cars (including the pace car). Danica did damn near the same thing a few seasons ago. She lost control under caution, spun and hit the wall just feet from a safety vehicle. I don't really think there will be any sweeping changes as far as NASCAR is concerned. It was a freak accident. Only other thing I can think of, is that they tell the cars to stay on the apron when they are making their way back around the track under caution like that.