At 13 ft, we're looking at a grand total of 5.5 psi of water pressure meaing a total of 1.37 ATA. That would put air density at about 0.0745 lbm/ft3, which is a less than 1% increase of air density from sea level.
As others have already illustrated, the issue of pressure in relation to lung over-expansion injury stems from the change in pressure, not its absolute.
People have died in swimming pools on scuba.. ascending from kneeling in the shallows to standing at the surface. Shallowest recorded incidence of severe lung trauma was recorded on an ascent from 0.3m to the surface.
Given the split second in which a fatal incident could occur... what's your 'expert' strategy to ensure that you could prevent it? Qualified instructors deal with this risk to students, day-in / day-out.
No progression into deeper water will be made unless he can show competency at mask clearing, regulator retrieval, and buddy breathing in the 4 ft shallow end. We'll do progressions with that. Mask on, 5mm gloves on, mask off w/ gloves, blindfolded w/ gloves (only in the shallow end, where simply standing up takes you out of the water). The things I'll look for are open airways (blowing bubbles) and calm actions. If any panic is shown, we'll suspend it right there.
This is a fantasy, right? You are SERIOUSLY assessing yourself capable of teaching scuba, when you have virtually zero practical experience of doing the activity yourself?
You need to arrest this. Go visit a decent instructor and ask them to 'put you through your paces'. I'm sure there'll be a volunteer or two here on Scubaboard. The average professional instructor completes 3x your total logged dives in an average month... many do substantially more.
I don't care what you
think about your competence as a diver - I know you could be pushed easily to meltdown in 5 minutes. That's a promise.
But we need to focus more on real-life skills.
There is no 'we'. There are professional instructors.... and there is you... a noobie. If you've not noticed, you're in a minority of one... and rapidly losing any credibility on this forum.
You ascertain that you have some intelligence... so perhaps it's time to engage that grey matter and start listening to people. The ability to appreciate the limitations of your knowledge and formulate an effect self-appreciation being several key defining factors of intelligent behavior.
My $.02 about instruction.
Thanks, but it's not quite worth that much.
Would anything change if I had an instructor certification? No,..
Plenty would change as you gained experience. That's another promise. If it didn't, you'd never get past the door on a DM course, let alone instructor.
Personally, I don't give a toss about your self-delusions.... but what you're suggesting/advocating has a direct impact on the safety of others, who may be naive enough to believe your bravado. For their sakes... it's time you woke up and smelled the coffee.
