I f*** up and I am ashamed

[boulderjohn]

You really scared me. I will study the altitude aspect.

In the case I cited, the altitude of the dive was extremely high, and the dive frankly should not have been attempted. There is a good chance you will never be at that elevation, let alone dive it.

But I will help you look into it.

I assume that your DM course included training in Boyle's Law, mathematically represented by V1P1=V2P2. At sea level (surface P = 1 ATA), a 1 liter (or whatever) volume of air at 10 meters depth (2ATA) that is taken to the surface will double in size (1*2=V2*1=2). If the atmospheric pressure is 0.8 because of altitude (about 1,800 meters), then the equation is 1*1.8=V2*0.8=2.25.

 

[drrich2]

I was told to dive with as little weight as I could.

You may've run into some of the 'politics' of scuba diving. A comment lament is that OW students are over-weighted so they stay down (such as on the bottom of the pool for skills training and practice; on the forum you'll see teaching while neutrally buoyant, not on the bottom, advocated). I'm speculating that maybe, just maybe, your teachers have seen enough over-weighted new divers that they now wish to encourage people against over-weighting...and maybe somehow that went a little too far? I know you've long sense gotten the message on the weighing thing; just suggesting a possibility for why you may've heard different messages from different people.

 

[Raphus]

My DM course was one week long .But I had done the Rescue course before and it took two weeks.

Wow. OK that explains a lot.
A DM course is usually over 6.months.some are 2-3 Months and more intense.

My course was 6 months, around 100 dives and a lot of assisting in classes.
We had DMs do much less. But something like 40-50 dives were the minimum. Which is great.

We talked about this in another thread, maybe you want to switch your instructor. At least the DM course seems like a total scam to me.

 

[Dan]

One other thing that has not been mentioned here is finning style when you are in a cavern environment. We need to be aware of the possibility of silting out the area behind you with normal finning style and blinding your buddy right behind you. We tend to do a slow frog kick style to minimize the silting out situation. If you lead the dive, you may not be aware of it, but the diver behind you would be blinded by your bad finning style.

My first experience of this situation was when I went to 3m diameter L- shape tunnel in a lake with my dive buddy. The tunnel has 12m run from the entrance and bend 90 degrees to another 6m straight run to a sunken bus at exit. I thought it's a pretty simple swim through in shallow water and each of us had dive light. My dive buddy went in first. For the first 2-3m penetration, I still could see his silhouette in front of me. After 7m of penetration, I completely got disoriented by all the silting out caused by his fining style and blinded by the light reflecting back by the completely silt out situation. My thought was, as long as I went straight forward, I would eventually hit a dead end, which I did. However, I didn't know whether the tunnel bent to the right or to the left. I made a wrong guess (as usual) and turned to the left, and hit another dead end. Then I turned around, turned off my dive light and let the silt to settle down a bit for a couple minutes to see if there was a light at the end of the tunnel. I faintly saw light passing through the back of the bus at the end of the exit and slowly made an exit through the bus.

 

[Edward3c]

I don't do night dives for a reason that I won't tell you . Strong currents, I have had a few and I enjoyed it because I believed that the worst that could happen was that I would surface and be lost at sea. It happened last week and we had to surface swim for 2 hours. I never said that I was perfect. In fact, I want to experience all the possible sh*** to be a good diver.

Having done the DM course, you should be aware of the extra risks when night diving. Even if you’re not the one organising the dive you should still make yourself aware of the extra precautions required or call the dive.

Yesterday I was out with a group of experienced instructor trainers. The poor chap who did the planning was put through the grill, even though it was a simple pleasure dive to 35m with planned deco. There is no excuse once you have the qualification of saying, “It was the fault of the dive operator, manager or leader”.

 

[Dan]

I understand that very well. Not only did I use the valves but I moved my body. Ass up. I am willing to accept the concept that there was some air trapped in my BCD. But the question is: how could I get it out?

If you orient the vent port at the highest point of your BCD and pull the vent valve of that vent, you have a good chance to vent out the trapped air.

However, I won’t worry about it at this moment. Just add 2kg to your normal dive weight to overcome any trapped air in your BCD.

 

[GameChanger]

All of these questions have been thoroughly discussed in this and other threads. Yes, he is a DM. No, he is not diving in western Europe.

Thanks

 

[Dody]

In the case I cited, the altitude of the dive was extremely high, and the dive frankly should not have been attempted. There is a good chance you will never be at that elevation, let alone dive it.

But I will help you look into it.

I assume that your DM course included training in Boyle's Law, mathematically represented by V1P1=V2P2. At sea level (surface P = 1 ATA), a 1 liter (or whatever) volume of air at 10 meters depth (2ATA) that is taken to the surface will double in size (1*2=V2*1=2). If the atmospheric pressure is 0.8 because of altitude (about 1,800 meters), then the equation is 1*1.8=V2*0.8=2.25.

I learnt it at school and then in OW class.

 

[ginti]

ONE week training for DM, really?

I have never said that 1 week is enough in my opinion. Actually, I have already made clear that, in my opinion, DM training standards aren't good enough.

But these are opinion.

You cited a number. This isn't an opinion, it's a fact. I am asking where you found this information. I am really interested in industry's standards, so I would really appreciate if you could answer my previous questions:
Which agencies require 35 dives for a DM card? What about the others?

 

[Dody]

@Dody

Would you like to have the title of this thread changed to something a bit, uh, cooler?

Nevermind