Can't remember any episode that featured an "Escape Tunnel"! For my peace of mind this needs to go 50 to 100 yards away from the shelter and come up in a screened area! Various scenarios make this critical: Fire, fallen trees, debris block main door, above Vandals, etc. Several shelter builders listed on the sidebar feature escape tunnels in the larger, high-end units.
Building or buying a Bunker, some things to consider! Comments welcome!