F1 rules: although The Alfred is a 2 minute drive from the Melbourne Albert Park track, we had to be there and ready for any F1 race or practice plus be running for the start of the actual race.
When a marshal was killed by a loose wheel some years ago, I transferred the poor bloke only with the express permission of the race officials that we could be back for any further accident sooner than the response car would get there. Otherwise they were ready to stop the race until the backup helicopter arrived, not that there was a backup anyway