Diver vs DM Responsibilities

[mcohen1021]

I probably should not ask this question on here, but I just can not help but want a 3rd, 4th 10th opinion on this.

This will be a hornets nest for this forum I am certain...

Scenario: Diver with less than 100 dives. Dives exclusively with the same divemaster each trip. Her husband is a much more experienced diver. Everyone using computers.

Note: I was not there....

Day 1, dive #2, she tells me this: “I ended up in deco and spent 20 minutes at safety stop. Ugh”

After talking to her a while, more comes out her 2nd day of scuba:

Day 2 Dive 1: “The final five of us did it on the first dive today”

Day 2, Dive: “The second dive I was the only one and no one knows quite why I couldn't believe how long I stayed at 15'”

============

There is so much wrong here I do not know where to begin…

1. As her DM, do you make her stay out of the water for 24 hours based on that 20 min deco stop? (translation: fall back to the PADI dive tables rules)

2. Day two, dive #1, five divers go into deco? Then go on a 2nd dive an hour later? Is this DM irresponsibility? I would have benched them all.

3. Day two, dive 2, she has now deco’d 3x in a row…. Seriously, this is unreal to me as I have almost 30 yrs of scuba and never deco’d…

I understand that the ultimate responsibility for your own safety depends on you. But there are so many divers that rely on the DM to keep them safe (I never have). I personally have no problem telling a guide that I am low on time/air… Basically that I can’t go see what he wants to show me because I would exceed time and depth limits…

So what would you do as the DM? What rules apply – computer vs tables? I would have applied tables rules. To me, this has fail written all over it from both the diver and divemaster perspective. She for exceeding the limits, the DM for letting her continue. She is lucky she did not end up in a chamber, and I told her that...

Maybe the DM should have a policy to forewarn divers exceeding limits will sit out on subsequent dives...

 

[kmarks]

This sounds like a case of a bad DM leading bad divers.

"Diver with less than 100 dives" could mean anything from 5 dives, straight out of OW certification to 99 dives, which I would consider to be fairly experienced, especially if all 99 dives and the ones we are talking about are in similar environments (I wouldn't consider this diver experienced if the scenario were Great Lakes wreck diving and she had all 99 dives in the Florida Keys). I have fewer than 100 dives, ranging from cold, gross quarry water in Iowa to drift diving in Cozumel, but I would consider myself experienced enough to know my limits.

I don't think it is the job of the DM to be anything more than a guide; it is the diver's personal responsibility to monitor their own gas and NDL and nobody else's. When you complete OW certification, you should have demonstrated that you have the skills and responsibility to dive independently without killing yourself, and that includes recognizing your limits and ending a dive, or just not doing it, if it exceeds your abilities. I have never gone into deco, and I don't plan to, even if it means missing that one really cool thing; it's just not worth the risk to me. If something goes wrong, like I get caught up in a down current on the side of a wall and suddenly find myself 40 feet deeper than I planned, and I end up with a deco obligation, I will sit out the next day. Maybe I'm overly cautious, but I like my health and so does my family. You certainly won't see me in the water an hour later.

That said, the DM should also enforce safety rules. If a diver can't keep herself out of deco three dives in a row, as a DM (and I'm not one), I wouldn't allow her to dive with me again. At all. Clearly, though, this is not a good DM if 5 people on a dive went into deco without that being part of the dive plan. If that was part of the dive plan, that's fine, to each their own.

“The second dive I was the only one and no one knows quite why I couldn't believe how long I stayed at 15'” I think I can tell you why: She surpassed the NDL yesterday, which means she started today with a higher nitrogen load than anyone else, even after a deco stop, then she did it again an hour ago. Also, she clearly wasn't paying attention to her computer's NDL limit on any of those dives. It doesn't count down from 30 minutes NDL to a deco requirement immediately. I was always taught to never let it get below five minutes. If you get to five, go up a few feet.

So my long winded response boils down to the same thing you said: they both screwed up.

 

[mi000ke]

I agree with @kmarks about the divers having to take responsibility for themselves. I think of the DM as primarily a guide. I'm about to do my 100th dive, so only moderately experienced, but even since my earlier dives I have always been the one to tell the DM/guide when it was time for me to ascend or turn the dive or shallow up, or whatever was required for me to dive safely. I have never had a DM who did not respond appropriately, so I would agree with @mcohen1021 that the DM referred to by the OP was not acting in the best interest of the divers being guided.

 

[northernone]

I know some regional laws and dive operators will limit the divers to NDL diving and will expect their DMs to police the customers dive profiles. Others don't.

Here's some direct answers to perhaps spark discussion.

1. I wouldn't make another diver change their dive plan unless emergency intervention is needed/welcomed.

2. With every dive involving decompression, I'm less concerned with a two hour surface interval provided no one omitted necessary deco and everyone is asymptomatic. Emergency response protocol otherwise, if the diver (or all 5 of them) wanted emergency assistance.

3. Provided the proper redundancy, planning and support is there, staged decompression diving is perfectly normal. In some training disciplines it is introduced very early in the dive's experience and is unremarkable in some regions. However, I would expect the divers to follow their dive plan. If we're expecting to stay together I need to have my own gas reserves planned to match their deco obligations. Don't surprise me. Given this group has a lot of experience diving together this likely isn't a factor.

If a group dives a similar profile and one diver gets hit with 20 minutes deco and the rest only have 3 minutes. I would want to see if the computer is malfunctioning or set suboptimally.

In short, live and let dive.

 

[Edward3c]

First, divers either plan and dive on tables or their computer. Switching between the two is foolhardy if not impossible following multiple dives.

Going into deco without planning it is risky, because there might not be enough gas left in the cylinder.

 

[mcohen1021]

This sounds like a case of a bad DM leading bad divers.

I have to say, if I didn’t know this DM, I would agree with you. And the diver, well, a beginner. I would guess she had between 80 and 100 dives lifetime.

So my long winded response boils down to the same thing you said: they both screwed up.

I agree

so I would agree with @mcohen1021 that the DM referred to by the OP was not acting in the best interest of the divers being guided.

Thanks

First, divers either plan and dive on tables or their computer. Switching between the two is foolhardy if not impossible following multiple dives.

I should have mentioned, this is a recreational NDL level vacation diver. I understand not to switch between computer and tables, BUT, what is the rule then at this point? Does the 6 hour / 24 hour rule no longer apply when you go into deco bc you’re using a computer?

 

[outofofficebrb]

Because you were not there, I feel like we do not have a complete picture painted for us on what really happened. I’m not saying your account is incorrect or that you omitted information; I’m saying I think there may be some important details that would be interesting to hear if we had the DM’s account or your friend’s account firsthand.

As another poster mentioned, computers don’t just jump into deco. Your NDL slowly counts down at any given depth and changes as you change depths. If your friend were paying attention and checking, she would notice her NDL getting close to 0 and should have done the following things: alert her buddy, alert the DM, and also ascend slightly. A few questions come to mind: was she in fact paying attention, did she do that, and if she did, what was the DM’s reaction? Did he brush her off or did he ask the group to ascend to a depth that provided an acceptable NDL? Were they communicating with each other?

I have had this happen to me. Usually, the DM will ask the group to ascend slightly or will ask my buddy and I to ascend slightly depending on the dive conditions and arrangements. The DM will ask at a shallower depth how my NDL is at that slight ascent. It is up to me to communicate whether it is okay or not. Sometimes it’s a set number that is decided on during the briefing (e.g., don’t go below 5 min). Sometimes, it’s not discussed and as a certified diver, you need to know what you are comfortable with (2? 5? 10?) and how to communicate that.

Since only your friend went into deco on the first dive, it leads me to believe she failed in her responsibility to communicate and watch her NDL.

After the dive where your friend had deco, as the DM, I would have emphasized we are doing no stop, no deco diving and to watch your NDLs. On the subsequent dive where 5 of them ended in deco, my question is this: was anyone paying attention to their NDL? Did the DM ask everyone to follow and everyone complied without personal considerations to their dive profiles? Did the DM also get a deco obligation or was he diving a more liberal algorithm? After your friend needing required deco, I would be hesitant about the groups ability to watch their own NDL. I would be proactive to ask each diver how much air and how much NDL just to avoid surprises. I would also emphasize no deco, plan the dive, dive the plan.

Ultimately, it is the diver’s responsibility to frequently check air and NDL and to communicate this to buddy and the DM. Given events that happened on previous dives, it would have been prudent for DM to be proactively checking with their group instead of waiting for them to communicate it, if at all. If the group did communicate, and the DM still went on with the dive with no regard or concern, then that is obviously a problem.

I am surprised the DM didn’t bench because it is a liability for the DM and operator. If something were to happen, and it came up that they were going into deco repeatedly despite being asked not to and having it be the policy, and entered the water with the DM and operator knowing that this happened not once, but twice previously with it not being part of the plan and this diver is not trained for it, it could be an issue.

There are some things I would love to hear more detail on from your friends or the DM to hear their account.

 

[MaxBottomtime]

With less than a hundred dives I doubt her air consumption was good enough to get twenty minutes of deco on her second dive of day one, especially with a single tank, even if she was using a Suunto computer. Since she relies on a Divemaster I have doubts her deco information was correct.

 

[NorCalDM]

I don’t know I’m a little skeptical if she truly incurred a 20 minute deco obligation on the first dive? How deep for how long and for typical vacation diving with an 80 cu ft single cylinder did she have enough gas to first incure the obligation and second complete a 20 minute stop. To me something is a little off with the story and if not she needs to rethink her diving.

Edit: you typed faster than I did!

 

[kmarks]

With less than a hundred dives I doubt her air consumption was good enough to get twenty minutes of deco on her second dive of day one, especially with a single tank, even if she was using a Suunto computer. Since she relies on a Divemaster I have doubts her deco information was correct.

I don’t know I’m a little skeptical if she truly incurred a 20 minute deco obligation on the first dive? How deep for how long and for typical vacation diving with an 80 cu ft single cylinder did she have enough gas to first incure the obligation and second complete a 20 minute stop. To me something is a little off with the story and if not she needs to rethink her diving.

Edit: you typed faster than I did!

If I'm doing the math right, you can hit the NDL at 70 feet in 40 minutes (on a square profile), according to the PADI table. If you have an SAC of 0.4 (not unreasonable for a female in warm water - I average about 0.45 as a similarly experienced male in warm water), you'll hit that having consumed a bit over 50ft^3 of air. At 90 feet, you'll get there in 25 minutes and you've only used 40ft^3. That's only just hitting the NDL, and I don't know how long you have to exceed it to need 20 minutes of deco, but she's still got half her tank left. If she's using a very conservative algorithm, I can see it happening. Even more so if she's using a high capacity tank.