Somewhere in Nevada, a family has built a DIY underwater tent where they can literally stay under water for hours by the use of oxygen being held inside the tent.
Of course, you probably shouldn’t try this yourself unless you know a bit about scuba diving.
Jordan: Ya, we use a standard scuba tank to fill it, and replenish the air once it gets thin. A standard 68 cu. in. scuba tank will fill it almost twice. There are obvious safety concern with being in a bubble 20 feet down and all the oxygen being used up, so we try and play it safe—buddy system at all times, and when the air starts to get even a little thin we empty most of it and fill ‘er back up with fresh air.