I am interested im making an underwater respirator for depths no more than ten feet. My plans for the respirator are as follows:
long tube, that is above waterline connected to a pump, that pumps down to the respirator. it is connected to the respirator through a one-way valve. I used a small seltzer water bottle as the actual respirator. I cut off the upper half as the actual part. I looks like a cone. So the tube is connected to the bottle through a hole in the side with a one way valve (air in), held airtight by multiple ballons and rubberbands. I have put a mouth piece on the top of the bottle, where the threads are. On the bottom of the bottle, where I cut it, there are multible ballons spanning the distance with another one way valve (air out). When air is pumped to me, i can either breathe it, or let it flow through.
Does anyone know a web site where a design like this is explained in detail?
And, How deep is it dangerous to breathe pure oxygen (like 30 feet)?