LiteHedded
Contributor
18/45 wouldn't be my first choice for this dive. try it with 15/55 and see what the difference is.
I don't take it any deeper than 200' (...anymore). but that's just me
PSAI Narcosis Management course - 73m on air
- Thread starter Tortuga68
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18/45 wouldn't be my first choice for this dive. try it with 15/55 and see what the difference is.
I don't take it any deeper than 200' (...anymore). but that's just me
ucfdiver
Contributor
I was just picking a gas with similar deco properties (ignoring a higher ppo2 for a He mix). Best mix appears to be a topic of little concern in this course, wouldn't you agree?
OP
You don't find it ironic that part of your criticism of the course is it's breaking of conventional MOD/PPO2 limits, and then you suggest the instructors should use 18/45?
OP
15/55 is a hypoxic mix, right? Can you breathe it at the surface?
LiteHedded
Contributor
it becomes normoxic at like 2 feet or something silly like that
ucfdiver
Contributor
Not at all...in context here, you guys have clearly chosen to ignore the ppo2 standard, and I was stating that deco is a poor reason to double the instructors narcotic depth...you could at least solve one of the major issues.
DevonDiver
N/A
18% gives you a ppo2 of 1.49....and that's certainly preferable to the ppo2 you went to using 21% (air)
MOD for 18% is 67m. (1.4)
MOD for 15% is 83.9m (1.4)
However, 15% is not a normoxic blend (stated ceiling at 2m), so there would be more issues with travel mix requirements, gas sharing etc etc
Personally, I think an 18/45 would be a reasonable option for the instructor concerned. Especially as most tech agencies are now supportive of normoxic trimix use in the deeper portions of extended range training.
There just seems to be no valid reason not to use a sensible trimix blend for supervising a 70m dive.... the only options I can assume are saving money on helium costs or he is a deep air junkie. Neither of these options displays any regard for the safety of the student.
MOD for 18% is 67m. (1.4)
MOD for 15% is 83.9m (1.4)
However, 15% is not a normoxic blend (stated ceiling at 2m), so there would be more issues with travel mix requirements, gas sharing etc etc
Personally, I think an 18/45 would be a reasonable option for the instructor concerned. Especially as most tech agencies are now supportive of normoxic trimix use in the deeper portions of extended range training.
There just seems to be no valid reason not to use a sensible trimix blend for supervising a 70m dive.... the only options I can assume are saving money on helium costs or he is a deep air junkie. Neither of these options displays any regard for the safety of the student.
Tortuga -- Over the past couple of days, I believe I've read every post, especially yours so I hope I didn't miss the answer to the following question. (If so, I apologize in advance.)
This course, as I understand it, is designed to teach "narcosis management" through a series of increasingly deep dives. Other than a stepped approach to depth, is there anything in the course that actually teaches a diver how to "manage narcosis?" If so, what are the "tips" (or whatever they might be designated) that you were taught?
This course, as I understand it, is designed to teach "narcosis management" through a series of increasingly deep dives. Other than a stepped approach to depth, is there anything in the course that actually teaches a diver how to "manage narcosis?" If so, what are the "tips" (or whatever they might be designated) that you were taught?
OP
I thought you guys were here to save me from myself and my instructor, and here you are recommending these unsafe mixes...
So now it doesn't need to be 'safe', just 'safer'?
So it's okay to break the rules, so long as you only break them a little bit?
Anyway, I think you get my point
How about someone posts the comparative runtimes, I really would like to see them
So now it doesn't need to be 'safe', just 'safer'?
So it's okay to break the rules, so long as you only break them a little bit?
Anyway, I think you get my point
How about someone posts the comparative runtimes, I really would like to see them
OP
Hi Peter, I've mentioned quite a few of them already, hopefully you'll find them in the thread; perhaps you might have missed some of my posts in between the encouraging contributions of our fellow SB.com members
Otherwise sign up for level 1, I gaurantee it won't kill you. Hell, you might even enjoy it. Send me a PM if you want further information
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