This kinda goes along with my other thread (Do Yo feel the need to breathe) but this time does not involve air expansion in the lungs on ascent. I have always dived with the knowledge/understanding that, since your useable tank air will increase as you ascend, you would still have enough air to breathe, even if you totaly ran out of air at depth. I was trained to use the old "J" valve (reserve) & still feel that it provides a bit of additional safety that can't hurt. (of course, you must make a habit of checking that the operating rod is cocked a few times during your dive to be safe, but that is very easy to do...... The few times I have used the "K" valve
I have to fight the habit of reaching back (every so often) with my left hand to check the position of the operating rod!<G>) My understanding has always been that if you feel that ...getting hard to inhale....signal (that means you are running low on air) that ascending will enable you to keep breathing normaly, all the way to the surface. (The "J" valve reserve merely enables you to have enough air to breathe should you have to swim level or descend a bit (if you are in say a wreck or cave) before you can ascend. Isn't this correct?
I have to fight the habit of reaching back (every so often) with my left hand to check the position of the operating rod!<G>) My understanding has always been that if you feel that ...getting hard to inhale....signal (that means you are running low on air) that ascending will enable you to keep breathing normaly, all the way to the surface. (The "J" valve reserve merely enables you to have enough air to breathe should you have to swim level or descend a bit (if you are in say a wreck or cave) before you can ascend. Isn't this correct?