nuclear submarines are used every day and keep or sailors safely summered under water for as much as 6 moths at a time,so i was thinking to make some safe storm shelters on land and at sea,under the ocean during a hurricanes they ,could presumably be under the ocean,or on ones land they have to be built with i call sub standards,not meaning below grade or does it? yes know there and idea below grade !! ok i made like a single wide mobile home that was water tight with like a submarine hatch for an entrance,the ventilation shafts were cold rolled steal of different dimensions pressed into each other like inner and the outer dimensions matching perfectly being pressed into one another un till i made a shaft that could with stand any hurricane storm floating trash colliding in to them,like a car hitting a tree the tree wins every time a car crashes into them right. well this was one of the biggest obstacles to over come in the under ground summered hurricane storm shelter.then as a finished product the ventilation shafts were disguised as palm trees ,preferably untrimmed with the dry ed up looking palm leaves. this is where there was fuel tanks one 1 shaft and on the other of witch there were 2 was a water storage tank for a emergency fire sprinkler system. the sprinkler heads are in the mechanical room where the generator hvac systems are and in the kitchen over the cook top . it is a steal shoe box basically with floor plans like a single wide mobile home,steal stud frame work with sheet rock walls 1/2 inch and ceiling all ceramic or clay tile on the floors twin murphy beds entertainment centers computer desk,and full kitchen and bath,with storage room off the small mechanical room that had plenty of shelves and Freezer for food storage, the sheet rock in the mechanical rooms were 5/8 inch walls and ceiling times 2 doubled up making a 2 hour fire wall also a fire door and emergency smoke evacuation vents.the vents went way down into the ground like a male and female pips fitting into a flag pole these were set in cement .in fact the whole shelter was set in like a cement tomb then back filled with rocks for drainage and to inhibit rust from penetrating the water proofing layers on the out side of the shelter,it was like a in law apartment under ground ,good party room after the bars close no one could hear you under ground turn up the music and enjoy,had full security cameras,as to watch the storm as it passes over head.and a emergency response team after the storm in case the entrance ever gets covered from the storms after mass.there's more but that is what i wanted to do. think it can be done ,is it possible.what do you think.