First dive at 40 meters - Newbies recreational

[Jcp2]

Well he wrote he had one mandatory at 20m so how do you explain another at 12m for 2 mins and the final safety stop at 5m?

Students riding NDL on a first dive to 40m on training dive? Say it aint so

Thanks for clarification about the Suunto.

My Cressi also had a deep safety stop as an option that comes turned on when first using the computer. It’s stated in the manual that it was an option that some diving philosophies prefer, so I turned it off.

However, this was after a couple of deep dives with an instructor that did what I now know from SB as Pyle stops, where we stopped halfway up the anchor line for 2 minutes (40-50 ft) and then again at 15 feet for the second safety stop,

 

[Dody]

Part 1 of 2:

Red flag: I will only do a depth progression past 30m on a one-2-one basis.
Red flag: who was the dive leader for the dive? You, your wife or the DM?

Red flag: Had you done the gas management calculations to confirm there was enough gas to get you back to 5m whilst sharing one cylinder.

Red flag: If you diving deep you should go straight there not mess round in the shallows.

Red flag: NN starts its narcotic effects from 15m onward. I get students to complete a prepared ‘noughts & crosses’; they can’t believe what they wrote when on the surface,

Red flag: What decent rate did you plan. Tables can use anything from 10m/s to 30m/s (BSAC 88), if you don’t stick to them you’re diving outside the plan.

Red flag: Someone on the surface is of no use to your during the dive. All they can do is report you are missing and your entry point.

This is one of the signs of NN.

Red flag: You were likely overweighted for the depth, insufficient gas in your BCD, or you had dumped too much.

Red flag: At 20m your slow tissues are still on-loading which will increase the decompression requirements at shallower depths.

Red flag: What did they do to made you think they were managing the dive?

Red flag: You were diving a ‘hope it works’ dive, no gas planning.

Red flag: I’ve had depth gauges out by 40bar, you could have been on a near empty cylinder.

Red flag: You got away with it, but you’re in line for a Darwin Award if you don’t develop the skills to plan and execute dives. See what @Storker said about “Normalization of deviance”.

You did not read. The gas planning was done. You might question the assumptions but the gas planning was done and proved right. In fact, at the end, we had over 50 bars than expected.
One to one no agency standard. We were 2 to 1 while SSI and PADI state 4 to 1.
The leader was the DM. Does not mean that I can’t make my own calculations.
10 m/s descent . We plan for much slower than that.
What about following the bubbles? The guys do it very well. I remember one dive at 20 meters or so. One of the boat guys dived and next thing I know, he poked my shoulder showing me the direction where he believed the sharks were. Without scuba.
No overweight at all. 4 kg for 70. Now, if you study Archimede, there is very little impact of the depth. If you are properly weighted for 30m, you are properly weighted for 40. Pressure will only very slighted reduce your volume.
Depth gauges, at least mine, is calibrated to be conservative not the other way around. Given that we had 100 bar safety, I think it is ok.
Sorry to say that but most of your red flags seem to me like wanting to make an impression.

 

[johndiver999]

Following bubbles.. I assume that means that the boat driver who is following you will be available to throw you an extra tank if you miss a safety stop and come to the surface calling for assistance.

That is something I do as well, but it is a plan C or D and not something I really expect to be available.

When drift diving on a more aggressive dive, sometimes we like to have a freediver, come down 20-30 feet and check on our stop, with the intent to be able to deliver some extra gas if needed, It is a nice luxury, but not something I depend on. Obviously not practical if you have only one person on the boat.

 

[scubadada]

Hi @Dody

That was a very "interesting" dive for you and your wife. You were brave to post it on SB for analysis. You have been given a lot of very valuable feedback, from which you can learn.

I'm still trying to fully understand the 3 stops you did on ascent, assuming that you are correct and did not enter deco. What dive computer are you using and how is it set? I'm assuming that the 1st, 2 min stop at 20 meters was a deep stop. Many computers offer an optional deep stop, many of us disable this feature. I'm assuming that your last stop at 5 meters was your safety stop. That leaves the 2 min stop at 12 meters, I don't think that @David Novo understands this either. Is your computer a Scubapro? I know that some of the SP computers offer profile dependent intermediate stops (PDIS). I can't come up with another optional stop for this depth.

Best of diving to you and your wife

 

[Tribal]

You started ascending with 150bar and you did came out with 40bar, so you used 110bar on the way up?
If your wife had a failure the surface would have been far away...

 

[Edward3c]

You did not read. The gas planning was done. You might question the assumptions but the gas planning was done and proved right. In fact, at the end, we had over 50 bars than expected.
One to one no agency standard. We were 2 to 1 while SSI and PADI state 4 to 1.
The leader was the DM. Does not mean that I can’t make my own calculations.
10 m/s descent . We plan for much slower than that.
What about following the bubbles? The guys do it very well. I remember one dive at 20 meters or so. One of the boat guys dived and next thing I know, he poked my shoulder showing me the direction where he believed the sharks were. Without scuba.
No overweight at all. 4 kg for 70. Now, if you study Archimede, there is very little impact of the depth. If you are properly weighted for 30m, you are properly weighted for 40. Pressure will only very slighted reduce your volume.
Depth gauges, at least mine, is calibrated to be conservative not the other way around. Given that we had 100 bar safety, I think it is ok.
Sorry to say that but most of your red flags seem to me like wanting to make an impression.

With 40+ years diving and 30+ as an instructor I don’t need to “make an impression”.
As I suspected, you’ve been diving long enough to know everything.
In your first post you state, “We surfaced with 40 bars without using the safety cylinder.” How is that a 100bar safety?
Buoyancy, your wetsuit will be compressed to 1/4 it’s thickness at 30m, and 1/5 @ 40m. Whilst this might not seem much it’s enough to affect you buoyancy.
Anyway, you’re so well trained why do you need to take advice.

 

[Dody]

You started ascending with 150bar and you did came out with 40bar, so you used 110bar on the way up?
If your wife had a failure the surface would have been far away...

Well. We stopped at 20 m and had fun. Then we stopped at 12 then at 5 where we had an extra cylinder. So, if my wife had had a problem, we would have had plenty of time to go straight to 5 m.

 

[Dody]

I a

With 40+ years diving and 30+ as an instructor I don’t need to “make an impression”.
As I suspected, you’ve been diving long enough to know everything.
In your first post you state, “We surfaced with 40 bars without using the safety cylinder.” How is that a 100bar safety?
Buoyancy, your wetsuit will be compressed to 1/4 it’s thickness at 30m, and 1/5 @ 40m. Whilst this might not seem much it’s enough to affect you buoyancy.
Anyway, you’re so well trained why do you need to take advice.

I am not questioning your knowledge but your attitude. A few of my PhD colleagues are the same. They might have big heads bot they are poor teachers.

 

[johndiver999]

Everyone is stuck at home for the Holidays and is grumpy. Give the guy some slack.

He has been diving for 45 days or something and calls himself a newbie. He's receptive to suggestions and has solicited them. It sounds like his training may be a little weak, it is going to take some time to grasp that.

Merry Christmas!

 

[Dody]

And

I a

I am not questioning your knowledge but your attitude. A few of my PhD colleagues are the same. They might have big heads bot they are poor teachers.

the 100 bar safety include the cylinder at 5 meters. I