how to pressure group / deep dive

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Scuba_Vixen once bubbled...
The scuba nazis are running wild... Befor drawing and quartering Adj and his instructor, let's all ..Stop, Breathe, Think, and then maybe, act. We weren't there, 10 feet isn't a big deal if it means a protected sandy bottom area to stop and do the math problem, this instructor probably does this same scenario at least 100 times a year, knows how long it takes, knows there's a ton of time left over before closing in on the ndl, could do it conservatively even if the computer failed, from knowing where in the scenario he is and how much air he has remaining. "Everyone should have their own computer" is mitigated by being under direct supervision, the instructor will always keep a student shallower than himself. Adj mentions swimming around a while, the skills part of the dive take all of about 5 minutes, so you know they came up to 80 feet for a while and then progressively shallower, all the while the instructor watching for narcosis and loss of bouyancy or control. I seriously doubt Adj was put in any undue danger, and the statistics for training related accidents support me.

Darlene

Well, Darlene I suspect this student wasn't in any danger on this dive. However he might be on his next dive since he hasn't a clue how to plan or even log the dive. He wasn't tought anything but now has a card that says he can go to a recommended max depth of 100 ft. It was a guided pleasure dive not a training dive.

You are right the instructor probably does this 100 times a year and unless he has a written waivor from the agency to do it this way there should be punitive or corrective action on the part of the agency for each and every incedent. The standards exist to insure the safety and quality of training of the student.

The student is required to plan his dive according to his tables of his computer and log the dive before having the dive signed off PERIOD The OW text and the AOW text both warn against diving some one elses computer. I guess this instructor doesn't see the need to encourage his students to follow safe dive practices.

I hardly believe I'm seeing people called "nazis" for wanting to see the training standards enforced. Read up on what has been going on a Gilboa. Three EMS responses in three weekends, one dead. Am I ever glad I'm getting out of this.

BTW, why would you need a sandy bottom to stop and do a math problem. Such tasks should be performed mid water. While not required by standards sitting on the bottom isn't diving.
 
Al Mialkovsky once bubbled...
Exceeding the limit of depth by 10 feet isn't unheard of.

Do you suggest that students refuse to do what the instructor wants and asks you to do
The original poster clearly did not have a clear picture of the intended profile or his deco status before the dive. My concern is not whether or not the instructor dove a safe profile. The problem is that the student was blindly relying upon the instructor.

Blind reliance is a bad practice. Unfortunately, blind reliance on others is what this instructor was teaching.
 
Wow, I thought I was asking a simple question, which apparently has a simple answer, which out of the 41 responses, it appears that the answer is that there is no way to determine the pressure group with the information I have.

It's 3 days later, I'm still alive and not bent (by the way, I also did a night dive that same day).....

I guess I need to buy a computer which should make things a little easier next time I dive (which may be back in Ohio, or may be on my next trip to the tropics - who knows).

As for the criticisms of my instructor - while I am not jumping to his defense (I am not an instructor and thus not equipped to spout standards, etc), I thought the guy was informative and kept me safe, especially since these were my first dives after being certified 2 weeks prior...

Thanks for the advice, those who gave it. I even managed to pull some wisdom out of the flames and will certainly consider this information in future dives...
 
adjuster-jd once bubbled...
As for the criticisms of my instructor - while I am not jumping to his defense (I am not an instructor and thus not equipped to spout standards, etc), I thought the guy was informative and kept me safe, especially since these were my first dives after being certified 2 weeks prior...

Thanks for the advice, those who gave it. I even managed to pull some wisdom out of the flames and will certainly consider this information in future dives...
/flame on: "He kept me safe" might be an appropriate statement for a non-certified discover scuba client to say. As a certified diver, you should be responsible for your own safety. That includes understanding and agreeing to the dive plan. That includes tracking your own N2 loading, whether by tables or computer. /flame off.
 
radagalf once bubbled...
The reason is that planning a dive is considered a "General Open Water Consideration", and as quoted below states:

4) Student divers must plan the dive using the Recreational Dive Planner or their personal dive computers, and conduct the dive within the limits of their plan.


I don't see that but I trust you that it's there. I just did my AOW and we spent a good deal of time going over the dive plan and talking about the considerations for exceeding 60' like increased gas usage, shortened NDL times, safety stop considerations, etc. to make sure that we all had it clear in our heads what we were dealing with. It just surprised me that a detailed plan and briefing weren't part of the required elements of the dive. We all had computers but did the plan by the tables anyway.

Thanks for pointing that out to me!

adjuster-jd: Trust me dives are bad news. I've done them, probably most people on the board have done them. I'm glad nothing bad happened to me, but I also won't be doing one again. Mine were in a situation very similar to yours where I was on vacation soon after my OW certification and figured that when I got the card I was told what I should do without supervision, there was a DM, that's supervision, I can do whatever I want. Looking back on some of those profiles and the depths I attained, I'm glad nothing bad happened to me and I'm glad nothing bad happened to you. While I've gone on to get my AOW since those dives, I've also backed up considerably in my conservativism and I now won't do ANY dive, no matter who's leading it, that I wouldn't do by myself, or feel comfortable getting out of if my "leader" is suddenly abducted by aliens.

Rachel
 
According to NAUI tables, fast and dirty by the way.

110', 30 min (required 7 min deco stop @ 15').

Ending letter "J".

Your SI 1:20 (blown by the tables, you would have 29 min of residual nitrogen, hence no dive to 90' by the tables)

Required SI 2:21 to get back on the tables with 2nd dive beginning letter "E".

This would allow 5 min bottom time (with 20min of residual nitrogen), to a max depth of 90'. Ending letter "G".

The NAUI tables would not have allowed the dives you did but a computer might have.

I personally would not have done those dives without planning by a computer or the tables if I didn't have computer. My instructor would not have allowed me in the water without planning them by tables anyway.

Plan your dive and dive your plan. :wink:
 
adjuster-jd once bubbled...
Wow, I thought I was asking a simple question, which apparently has a simple answer, which out of the 41 responses, it appears that the answer is that there is no way to determine the pressure group with the information I have.

As for the criticisms of my instructor - while I am not jumping to his defense (I am not an instructor and thus not equipped to spout standards, etc), I thought the guy was informative and kept me safe, especially since these were my first dives after being certified 2 weeks prior...


You are wise to not defend your instructor because while he took you on a safe dive profile, he didn't give you the tools or the knowledge to know that it was safe.
 
30 minutes at 110'....I doubt you could make an 80CF tank last that long(Im assuming 80CF) that deep.

Anyone consider that their bottom time might have been around 10 minutes at 110'? Maybe they took 3 minutes to get down. Thats 13. Then they started their ascent moving up to 60'. Say it took them 2 minutes. Thats 15. They hang out looking at the sights (as they actually decompress) for 5 minutes. Thats 20 minutes. Then they move on up to 20. Say another 2 minutes to ascend, thats 22 minutes. Swim around and suck down the rest of their tanks to 500psi for another 8 minutes (still decompressing). Total time.....30 minutes.

Been there done this profile. Deeper stops, or pauses if you will.....quit being a bunch of ninnys and find out the details before calling for someones head on a trident...sheesh!

Adjuster-jd, ask your instructor how long you were at 110' then how long it took you to come up and figure it from there. It comes down to "we" dont have enough info to accuratley calculate your dive. Sorry.....and to put things in a better perspective, please see the attached.....

:spaninq:
 
ScubaToneDog once bubbled...
30 minutes at 110'....I doubt you could make an 80CF tank last that long(Im assuming 80CF) that deep.

Anyone consider that their bottom time might have been around 10 minutes at 110'? Maybe they took 3 minutes to get down. Thats 13. Then they started their ascent moving up to 60'. Say it took them 2 minutes. Thats 15. They hang out looking at the sights (as they actually decompress) for 5 minutes. Thats 20 minutes. Then they move on up to 20. Say another 2 minutes to ascend, thats 22 minutes. Swim around and suck down the rest of their tanks to 500psi for another 8 minutes (still decompressing). Total time.....30 minutes.

Been there done this profile. Deeper stops, or pauses if you will.....quit being a bunch of ninnys and find out the details before calling for someones head on a trident...sheesh!

Adjuster-jd, ask your instructor how long you were at 110' then how long it took you to come up and figure it from there. It comes down to "we" dont have enough info to accuratley calculate your dive. Sorry.....and to put things in a better perspective, please see the attached.....

:spaninq:

Ah...but We do know the max depth allowed by standards is 100 ft and we do know that the purpose of this training dive is to teach the student how to do something other than play follow the leader and we do know that the student is to plan the dives using their own computer or tables and we do know that the time at which they left 110 doesn't matter because bottom time ends when you begin your ascent directly to the surface or safety stop when calculating with tables.

Don't we know those things? If not explain where my interpretation of the training standards went wrong please. And...if your an instructor maybe you could give some insight into you amazing comfort level of tolorance for the blatant disregard for them.
 
ScubaToneDog once bubbled...
30 minutes at 110'....I doubt you could make an 80CF tank last that long(Im assuming 80CF) that deep.

Anyone consider that their bottom time might have been around 10 minutes at 110'? :spaninq:

We already know that. The problem is he was doing his deep dive in AOW, exceeding 100' and without the aid of the wheel or a dive computer in planning and executing the dive. It was such a cluster f* that he had to come here and ask how to log his dive since 30@110 was off his tables.
 
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