Dive Dangers; The Differentiation between "SOLO" and "BUDDY"

[jester1226]

Does your formula take into account those of us that dive solo with ponies to aid in OOA situations?

Perhaps it's important to recognise the difference between 'risk of an incident happening' (i.e. double chance of equipment failure) and risk of death because of that failure. Yes, a buddied diver has twice the risk of encountering an equipment failure - but the actual safety risk to that individual is less because there are contingency alternatives available with a buddy which safeguard them. A solo diver has half the risk of encountering an incident, but arguably much more safety risk should that incident occur.

for example:

x = chance of incident occurrence.
y = chance of resolving incident
z = chance of avoiding harm to the diver.

Buddy Team - 2x X 4y = 8z
Solo Diver - 1x X 2y = 3z

 

[DevonDiver]

Does your formula take into account those of us that dive solo with ponies to aid in OOA situations?

The factors are variable. y is the chance of resolving incident.

Appropriate redundancy, whether single or buddied, would influence that factor. So would training and experience. So would depth and other environmental conditions.

That said, all else being equal....until a self-deploying pony was invented, I'd suggest that y would usually be higher in a buddy team, than for a solo diver.

 

[Bob DBF]

Appropriate redundancy, whether single or buddied, would influence that factor. So would training and experience. So would depth and other environmental conditions.

That said, all else being equal....until a self-deploying pony was invented, I'd suggest that y would usually be higher in a buddy team, than for a solo diver.

The first paragraph not only contridicts your simplistic formula, but also your second paragraph as well.

"That said, all else being equal..." all else is never equal, especially when dealing with people.

For the record, I dive Buddy as well as Solo and am of the firm belief that anyone who dives solo because of "bad buddies" should take a good look at their own skills, solo as well as buddy. There are plenty of good reasons to dive solo, it should not be because of someone else.


Bob
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I may be old, but I’m not dead yet.

 

[markmud]

Hey All,

Sometime we humans overthink things. The choice to dive solo or with a buddy depends on the circumstances of the indivual event.

I choose to dive solo when my buddy option is a person who sucks down a 120 cf tank in 30 minutes. This person is a liability and not experienced and/or trained well. In this situation, I will dive a conservative dive plan and dive at the shallowist depth possible that still accomplishes my goal (I am a rec diver, plain and simple--I don't do overhead, deep/deep dives or deco diving). I don't need to dive that badly--diving to a great spot at 40 fsw is better than buddying-up with a liability and going to 110 fsw.

Sometimes, I am the liability for other more experienced divers whose dive plan goes beyond my training and experience level. In that case I will dive below the boat or use a shallower profile and dive solo. The risk of having a catastrophic issue that creates chronic life support issues at 45 fsw, in warm water, with no currents or surge issues, are slim when you are properly equiped and trained to use your redundant gear and SOLAS gear.

Every situation is different. A simple formula for quantifying risk wil not work. Subjective discretionary judgements must be made in some situations.

Buddy diving is a hard and fast rule for some, but I consider it to be religous dogma.

Use your best judgement and accept the consequences of your decisions.

If you follow religous orthodoxy by diving with an air-hog to the bottom of the Yukon at 105 fsw, don't blame the air-hog for your trip to the recompression chamber--blame yourself.
markm

 

[markmud]

The first paragraph not only contridicts your simplistic formula, but also your second paragraph as well.

"That said, all else being equal..." all else is never equal, especially when dealing with people.

For the record, I dive Buddy as well as Solo and am of the firm belief that anyone who dives solo because of "bad buddies" should take a good look at their own skills, solo as well as buddy. There are plenty of good reasons to dive solo, it should not be because of someone else.


Bob
----------------------------------
I may be old, but I’m not dead yet.

Hey Bob,

I am cofused. Am I supposed to risk my life to dive with a bozo so that the bozo does not get hurt?

I dive for fun, I am not an instructor, and I don't dive to save lives. I know instructors who flash thier AOW card when diving for pleasure, because divemasters will pair the instructor with a poorly trained buddy. If the divemaster does not know a diver is an instructor, he won't assume that the instructor will bird-dog a poorly trained diver. The instructor is not there to keep someone else safe. He is there for pleasure--his/her pleasure!

Let the divemaster keep the poorly trained diver safe. He/she is being paid to perform that task. I am not.

Did I misunderstand your post?

markm

 

[Bob DBF]

Did I misunderstand your post?

markm

May be.

I have a number of positive reasons to solo, including spearfishing, photo, buddy can't make it, just wanting to follow my nose, or the solitude of a solo dive. If I don't have any particular solo goal, I will dive with anyone once, may be more.

In the solo threads over the time I've been reading, divers have given "bad buddies" as the reason to solo dive, usually by new divers, and my contention is that there should be a different reason to solo. As a solo diver you need to have a honest assessment of your skills and I believe anyone who thinks that everyone else is a bad buddy needs to reassess.

You have a valid point about diving for your pleasure, and not wanting to do the divemasters job. One time as I was heading out with my camera, the DM asked me to babysit a diver so I asked how much he paid, he told me to get off the f'n boat. On the other hand we knew each other and I had taken out kiddies before so he let me back on the boat.


Bob
------------------------------------
A man's got to know his limitations.
Harry Callahan

 

[NAM001]

HI MARK,

I must say I dont think that Bob is saying what you are reading or trying to read in to his comments. I agree with him that if the reason for diving solo is task related ,photo op, solitude, personal preference ect, then that is ok. If however if the sole reason for diving solo is that you believe buddies (which are now all) are a liability,(insinuates that you are better than all other divers) then you have to step back and think about why all divers/buddies are a liability and perhaps explore the possibility that others divers are ok and that maybe YOU are not. And that if you are the problem ,then you are possibly not fit to both buddy with or to dive solo.

I think it is safe to say that no one here is so apt at diving that all others become by default dangerous. If one were so skilled they 1. would not be on this board engaging with such ineptness to begin with, or 2. so deeply affiliated with the "its thier way or no way" that no one pays them any heed to begin with.

There are many on here of which i could file in in one of the above catagories, but Bob is not one of them. The DBF in his name says he has been around awhile and is not only team player but is confident of his skills enough to not only safely dive buddy or solo, but also knows when it is appropriate or necessary to do so.

Given that i am sure you missunderstood his position.

Keith Also a DBF'r

Hey Bob,

I am cofused. Am I supposed to risk my life to dive with a bozo so that the bozo does not get hurt?

I dive for fun, I am not an instructor, and I don't dive to save lives. I know instructors who flash thier AOW card when diving for pleasure, because divemasters will pair the instructor with a poorly trained buddy. If the divemaster does not know a diver is an instructor, he won't assume that the instructor will bird-dog a poorly trained diver. The instructor is not there to keep someone else safe. He is there for pleasure--his/her pleasure!

Let the divemaster keep the poorly trained diver safe. He/she is being paid to perform that task. I am not.

Did I misunderstand your post?

markm

 

[vladimir]

for example:x = chance of incident occurrence.y = chance of resolving incident z = chance of avoiding harm to the diver.Buddy Team - 2x X 4y = 8zSolo Diver - 1x X 2y = 3z

I see what you are trying to say here, but this mathematical representation says something else. Well, it says you've forgotten algebra. Me too, for the most part, but once we see that z=xy, it is confusing to find in the very next equation that it also equals 2/3 xy, bringing us to the inescapable conclusion that 1=2/3.

Let's make up some numbers, since we've all forgotten algebra. Let's say the probability of an individual diver having a problem on a dive--one that would be deadly if not resolved--is 2%. The chance of a buddy team developing such a problem would be:

98% * 98% of the time, or 9604 dives out of 10,000, neither diver has a problem;
2% * 2% of the time, or 4 dives in 10,000, they both have a problem;
the remaining 392 dives, one of them has a problem.

​

Let's say that each diver has a 95% chance of resolving a problem of this sort (or a 5% chance of not resolving it). For a solo diver, 5% of his problem dives, or 1 dive out of a thousand, he ends up dead. For the buddy team, both buddies have to blow the resolution, which happens .25% (5%*5%) of the times that a problem emerges, which is on 3.96% of the dives. So a buddy diver turns up dead approximately once every 10,000 dives, based on these simplistic assumptions.

You could argue that a diver has a better chance of resolving a problem when it's his buddy that has the issue (certainly true for entanglement), skewing the odds further in favor of buddy teams. Of course, I am assuming actual functioning buddy teams, not same-time, same-ocean buddies.

 

[rx7diver]

I see what you are trying to say here, but this mathematical representation says something else. ...

Vladimir and DevonDiver,

I have a different take on your computations. Here it is:

Define the events:

A = "Diver #1 (Andrew) has a critical problem"
B = "Diver #2 (Beatrice) has a critical problem"


These imply the following events:

AUB = "A or B" = "Either Diver #1 or Diver #2 has a critical problem"
A&B = "A and B" = "Both Diver #1 and Diver #2 have critical problems"
A' = "Diver #1 does NOT have a critical problem"
B' = "Diver #2 does NOT have a critical problem"


Okay. Your assumptions are:

1. Pr(A) = 2% = 0.02 = likelihood that Diver #1 has a critical problem
2. Pr(B) = 0.02
3. Statistical Independence (i.e., whether or not Diver #1 has a critical problem is not affected by, and has no effect on, whether or not Diver #2 has a critical problem). NOTE: This is a critical assumption, and might NOT apply.


Okay. You are interested in comparing the following two scenarios:

1. Pr(A, and problem is NOT resolved), in the case when Diver #1 is diving solo.
2. Pr(AUB, and problem(s) is/are NOT resolved), in the case when Divers #1 and #2 are buddy diving.


Then solutions using your assumptions are:


Solution to Scenario #1:

Pr(A, and problem is NOT resolved)
= Pr(problem is NOT resolved | A) x Pr(A)
= 0.05 x 0.02
= 0.001 = "1 chance in 1,000"


Solution to Scenario #2:

Pr(AUB, and problem(s) is/are NOT resolved)
= Pr(A&B', and problem is NOT resolved)
+ Pr(A'&B, and problem is NOT resolved)
+ Pr(A&B, and problems are NOT resolved)

= Pr(problem is NOT resolved | A&B') x Pr(A&B')
+ Pr(problem is NOT resolved | A'&B) x Pr(A'&B)
+ Pr(problems are NOT resolved | A&B) x Pr(A&B)

= Pr(problem is NOT resolved | A&B') x 0.02 x 0.98
+ Pr(problem is NOT resolved | A'&B) x 0.98 x 0.02
+ Pr(problems are NOT resolved | A&B) x 0.02 x 0.02

= ????


At this point, you cannot proceed to a final solution for Scenario #2 without making additional assumptions, since all you "know" (or believe) is:
Pr(problem is NOT resolved | A&B') < 0.05 (under the tacit assumption that two heads are better than one when it comes to solving a single critical problem), and
Pr(problem is NOT resolved | A'&B) < 0.05 (under the same tacit assumption).
In particular, you do NOT know Pr(problems are NOT resolved | A&B), the likelihood that the divers will NOT resolve simultaneous critical problems (i.e., the divers each simlutaneously has a critical problem).


I hope this helps. (Beware, it's early here, so I might have made a mistake!)

Safe Diving,

Ronald

 

[vladimir]

In particular, you do NOT know Pr(problems are NOT resolved | A&B), the likelihood that the divers will NOT resolve simultaneous critical problems (i.e., the divers each simlutaneously has a critical problem).

Assume that during the 4 times in 10,000 that each member of the buddy team is faced with a critical problem (not necessarily simultaneously) they do no worse than 2 solo divers. Why assume otherwise? It doesn't have a material impact on the 1-in-10,000 deaths estimate, so I left it out in the interest of simplicity. The point of the exercise was not to arrive at a meaningful estimate--impossible with simplistic assumptions and no data to refine them--but rather to demonstrate that, given those simplistic assumptions, the buddy team comes out much better.