Look into ROCK BOTTOM calculations.I have had several people, in two contexts, suggest that a turn or turnaround pressure of a 100 bar is a thing.
Does anyone have practical examples of when that would be the case in simple single tank diving?
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Look into ROCK BOTTOM calculations.I have had several people, in two contexts, suggest that a turn or turnaround pressure of a 100 bar is a thing.
Does anyone have practical examples of when that would be the case in simple single tank diving?
It's called the rule of halves.I am after whether there is a short cut like ‘rule of thirds’ or ‘be on the boat with 50 bar’ which is ‘turn at 100’ that I was not previously aware of.
I understand how to plan a dive properly to have enough gas to get a diver and an OOG buddy to the surface by doing the maths.
I am after whether there is a short cut like ‘rule of thirds’ or ‘be on the boat with 50 bar’ which is ‘turn at 100’ that I was not previously aware of.
Rock bottom calculation could easily have 100 bar as turn pressure for a dive profile.
Can you give an example? I am wondering if this is a language thing. By ‘turn’ do you mean pressure at which to leave the bottom? Or actually turn back?
2. Rule of Halves: You are traveling away from your starting point and would like to return to your starting point, but if you don't make it, the worst consequence is a surface swim.
In those cases, divers are usually planning to be near the surface at the end of their dives. In fact, it is a navigation technique, as I will explain. If you turn at half pressure and gradually ascend, you will be very near the surface at 60-70 bar, so there is no need to plan for more reserve. If, on the other hand, you are planning to get back to a point from which you will make a more serious ascent, you will want to plan a reserve, subtract that from the total, and plan your halves on the rest.In this case how is the turn pressure (being when the divers start to retrace) calculated? Is is it half of the available gas for the dive, ie start gas minus ascent reserve? And if so, to what degree do people assume this is half a cylinder?