A DIR spin on an old question

[Anti-Hero]

No, because if you're not diving close to the MOD, then you're not using the best mix

Sorry, but I disagree with this statement. Nitrox is not only to extend bottom time, which using the "best mix" is intended for; the highest F02 at a set PP02.

Many people dive recreational nitrox from 22-40% 02 on shallow dives nowhere near 1.2-1.4 PP02, simply to reduce nitrogen uptake. Less nitrogen on-gassing is ALWAYS a benefit.

 

[Dtaine]

Yes, but if you still have nitrox available, why would you be switching to your pony?

I'd switch to it if my back-gas became inaccessible due to equipment failure.

No, because if you're not diving close to the MOD, then you're not using the best mix

32% might not be the most efficient mix at all recreational depths, but I can lower my EAD without pushing the MOD.

These are two examples of why this isn't the right forum for you to get the answers you're looking for - it seems to me that you're trying to apply rules you don't fully understand to a scenario that the rules weren't designed to cover

I really don't think you understand why I posted here - I might have been better off just PM'ing some members this question.

DIR is designed as an all-or-nothing approach, not take some bits and ignore the others. By all means adopt some DIR practices to your rec. diving, lots of people do (long primary hose, BP/W, bungied secondary etc), but there's really no point asking for DIR validation of it

I understand that DIR really is all or nothing - ppo2_diver seemed to get to the basis of the question - I posted it here not for validation, but as a question for those who I'm more confident have a greater understanding of gas management

Look, what you're missing in your "what are the DIR rules" approach to this is that DIR is primarily about team diving.

There is almost no end to the number of problems with slinging a pony with air in it from the perspective of team diving. Because you don't have a DIR buddy? Because you haven't properly calculated "rock bottom" (aka: minimum gas) for a 100'+ dive? Because its a cheaper way to redundancy (vs. doubles)? Because you can't afford an EAN 32 fill? You are planning to use air at 130' to "solve" an OOG situation (for you or someone else)? They used to use the term "nickel rocketry" to describe the thought process of skirting safety protocols to save money, maybe do a google search with site:scubaboard.com in the search terms.

I really don't think you get what I was asking - I would love not to put air in the pony and to avoid air diving at 130 feet. It's why I'm going the way of Nitrox. I'm not looking to skirt safety in any area, but rather to add to it in a sensible manner.

Maybe you just have to realize that its not possible to do some of the above dives as DIR dives. Its pretty hard to do a DIR dive without a DIR buddy (I struggle with this locally where there is nobody else with a DIR mindset). We haven't even opened the discussion of doing the second dive on a 40 minute SI....

The case can be argued whether you could reasonably dive air on a relaxing 30' warm water reef dive, but I don't think you can make a similar argument for 130' on a single tank with no DIR buddy and an air in a pony bottle in place of redundancy. They used to say, "There are no DIR divers, only DIR dives." I don't think like the above example sounds anything remotely like a DIR dive. Maybe the dives you are doing today with the buddy/training/skills/equipment you have today aren't compatible with DIR. That's a tough thing for some people to digest and it drives some people away from DIR. Its not for everyone, n'est-ce pas?

Again, I'm not diving to air on 130. I did once and won't do it again. You really do not get what I was asking.

Sure, because it's extra "stuff" and doesn't get you anything.



You're really looking for a DIR answer to a non-DIR question. It's like asking "What kind of cheese can I put on my bacon cheeseburger to make it kosher?" The "DIR" answer would be "Don't dive with insta-buddies"

Given this, I'm wondering as to the DIR diver's "next-best" solution. Is it to use a pony, to use a y-valve and two first stages? I'm not asking for the DIR solution, but rather a logical solution from DIR minded divers, there's a difference. If everybody just wants to say, "well you should get good buddies" then fine.

If you dive with someone you trust, and have both done the necessary gas calculations and are both ready and able to share gas if needed, you won't need the pony because the person you're diving with, by definition would have reserved all the gas you need and would be right there next to you in case you have a problem (not just OOG).

I used to dive with a pony all the time, however after spending the summer doing Adv Nitrox/Deco training with my buddy, I've realized that it's much safer having him around than an extra tank. A pony won't have a line cutter out when you send up a lift bag (in case you get caught) or have a regulator right in front of your face, ready and waiting if you have some sort of air delivery problem, or stop you when you're about to do something dumb.

If you're diving with someone you don't trust, it's by definition not a DIR dive, since you're now essentially a solo diver with the extra liability of someone who may run out of air, not maintain your reserve gas or do other weird stuff at any time.

Although this will probably sound elitist, my solution to insta-buddies is to not dive with them on non-trivial dives. It keeps my stress level down.

Terry

While I would love to ditch all insta-buddies and simply dive with a competent team it's not what I'm able to do on 80-90% of my dives. All I'm looking for is the "best" solution other than ditching insta-buddies. I was hoping to get some input from divers who think with an approach I consider sensible and safe, that's why I asked it in this forum (it's not about the DIR answer, but rather the opinion of DIR divers), instead I've essentially been advised to take the question elsewhere.

 

[John_B]

I don't get to do all of my dives with DIR buddies either. But I do put limits on the dives I will do with an insta-buddy. IMO, 100' is the wrong depth to be with a buddy you can't/don't/won't trust. Its bears repeating:

The dives you may be doing today -- with the buddy/training/skills/equipment you have today -- might not be compatible with DIR.

 

[Dtaine]

...
The dives you may be doing today -- with the buddy/training/skills/equipment you have today -- might not be compatible with DIR.

I fully get this, but it's similar to this thread: http://www.scubaboard.com/forums/dir/261249-first-stage-flooding-possibly-how-avoid.html, which I posted some time ago where I was looking for input from divers who've already gone down the road I'm traveling. Rather than being ridiculed for my choice of thread placement the question was answered and it actually led to an interesting discussion.

 

[Bismark]

There's a reason I asked it here though. Every day since I discovered the philosophy of DIR diving I've been evaluating my equipment, learning ways to streamline my diving and make it easier, more relaxed, and to trump it all more safe. Never before have I seen a system where every gear decision and every aspect of the dive is evaluated and designed to be simple and efficient. In an ideal world I'd be diving single tanks with other divers who I know to be competent and safety minded, who dive as a team without the same day same ocean mindset. Unfortunately this isn't an ideal world and as such dives are done with people I've never seen before that day, with those who see no value in a buddy, and with those who take an all too carefree approach to diving. Because this is such I choose to carry a tank that otherwise I would see no need in having, and because I want to do it in the most efficient and most effective way I've asked those who follow what I see as the best approach to diving to give their opinion.

From everything I've read the DIR approach to diving involves being a thinking diver, adapting your equipment to dive in the most efficient manner possible; if I don't know who my buddy will be when I set out in the morning for a day of diving then I need to know that I have a equipment configuration that is setup to handle a buddy that doesn't care. If I approach that dive with a single-tank configuration and no redundant gas source other than my buddy's tank then I don't see how that's being a thinking diver, and I'm out of luck if I have a problem (yes I can self-rescue, but that could mean a CESA, which is less than ideal at 100-130 feet). If, however, I take the extra tank, my buddy bolts, and I have a problem, then I switch to the pony and turn the dive. Diving with an unknown buddy isn't DIR, but it's a situation I face all the time. The only way to solve this problem is to only dive with guaranteed buddies, or carry a pony, with the former method I'd be diving maybe once a month, with the latter I can dive once or twice per week.

As Doing It Right: The Fundamentals of Better Diving states, "A good SCUBA equipment configuration needs to carry through all diving; it should allow for the addition of items necessary to perform a specific dive (e.g., an ice dive, a cave dice or an open water dive) without interfering with or changing the existing configuration. Diving with the same configuration allows for the identical response to emergencies while reducing effective task loading due to familiarity. In other words, it not only helps solve problems, it prevents them." I will be diving with unfamiliar or possibly reckless buddies, which automatically makes those dives non-DIR, if I'm going to take a DIR approach to that problem, then adding a pony makes sense; it prevents a problem (I won't have to do a CESA, or I should say it becomes extremely unlikely), it adds very little complexity to the dive, and it doesn't interfere with anything. It's not DIR, but it's using the concepts of being a thinking, efficient diver, to manage an already non-DIR situation.

If I'm flamed for this thinking I won't be surprised, and it won't affect my diving or my approach to it; all I'm looking for is feedback, I'm not looking to troll or offend, if the question's not welcome here I'll freely move it elsewhere.

-Dave

Becoming a thinking diver starts well before you enter the water. In the case above, you just don't do those types of dives. Period. Stay home, watch TV, plan your next DIR dive with similar minded teammates. Carrying a pony bottle is incompatible with DIR diving. Period. You won't find a DIR diver worth his salt telling you how to implement the use of a pony bottle to make dives "more DIR".

"I will be diving with unfamiliar or possibly reckless buddies, which automatically makes those dives non-DIR, if I'm going to take a DIR approach to that problem, then adding a pony makes sense" DIR is not a buffet where you get to pick and choose from the menu and still have a DIR meal. It is an a la carte meal where everything is designed to work together to provide you the most balanced meal. If you are diving DIR, you do not dive with reckless buddies, thus avoiding the whole problem of pony bottles and how to make them "DIR". The system does not work piecemeal and you will find this makes more sense to you the more you use the complete system with similar minded divers. Thus, the answer to your question is you can not do DIR dives with a pony bottle. If you still choose to do these dives then they are not DIR dives and no amount of lipstick will make a pig look good.

 

[Bismark]

Given this, I'm wondering as to the DIR diver's "next-best" solution. Is it to use a pony, to use a y-valve and two first stages? I'm not asking for the DIR solution, but rather a logical solution from DIR minded divers, there's a difference. If everybody just wants to say, "well you should get good buddies" then fine.



While I would love to ditch all insta-buddies and simply dive with a competent team it's not what I'm able to do on 80-90% of my dives. All I'm looking for is the "best" solution other than ditching insta-buddies. I was hoping to get some input from divers who think with an approach I consider sensible and safe, that's why I asked it in this forum (it's not about the DIR answer, but rather the opinion of DIR divers), instead I've essentially been advised to take the question elsewhere.

As I mentioned above, DIR is not a buffet and there is no DIR "next best" solution. You will not get a non-DIR answer from a DIR diver. By definition, the only solution you will get from DIR divers is a DIR solution, and no where does a pony bottle factor in to this equation.

Dtaine, there are non DIR divers who are also sensible and safe. I suggest you expand your question to take in some of their opinions and thoughts by asking this question in another forum as well. Otherwise the only real answer you will get from DIR divers is that pony bottles are not DIR and can not be used within the framework of a DIR system. This will probably be more beneficial for you.

 

[TSandM]

The best solution is to try to find somebody locally who's intrigued with what you are doing, and groom that person as a steady dive buddy!

It's a catch-22 situation you find yourself in. The only DIR answer is, "Don't do those dives with those buddies," but if you are, for example, kidspot (the only DIR diver on Maui), you wouldn't dive much at all. The simple fact is that you can't be "DIR" without a team, even if it's a team of two. You can try to think through some of the principles of DIR diving, and adapt your own equipment and procedures as best you can in those directions, which is what I think you are trying to do, in recognizing that redundancy might be appropriate for some dives you are doing. But the deeper and more challenging the dives, the MORE the DIR approach would emphasize the importance of a good team . . . the catch-22 again.

So, given that carrying a pony to make up for poor buddies is completely outside the DIR system, I'd recommend putting Nitrox in the pony. You don't expect to use the fill, so you're only paying for one fill over many dives, and it would simplify deco status analysis if you were ever to have to use it.

Good luck with building a team. You really don't get either the full benefit or the full pleasure of what DIR diving has to offer, until you have a team to dive with.

 

[tep]

OK, I'm going to step outside the current conversation to see if I (we?) understand the question actually asked. I'll restate the question as I see it, and let's see if that changes anything.

1. OP worries about insta-buddies and wants more redundancy and safety for all his diving.
2. OP is not DIR, but likes the *part* of DIR philosophy that says that your diving rig should be *designed* to serve the purpose of the dive, so what's the best way to acheive #1 *by design*, using DIR "rig design principles".

I think that's a very fair question. I like a lot of DIR principles, like the necklaced backup, but I'm not diving DIR because I'm not part of a regular team, and I'm not doing the kind of diving that requires DIR.

For example, necklaced backups are starting to show up in non-DIR training. That's a specific area where DIR design principles can improve safety for all divers. I think OP is looking for the same kind of guidance on backup gas (or a backup buddy?) in instances where he specifically isn't diving in a team scenario with highly qualified buddies.

While this may not specifically belong in the DIR forums, it seems to be a reasonable question, at least to me.

 

[Web Monkey]

Given this, I'm wondering as to the DIR diver's "next-best" solution. Is it to use a pony, to use a y-valve and two first stages? I'm not asking for the DIR solution, but rather a logical solution from DIR minded divers, there's a difference. If everybody just wants to say, "well you should get good buddies" then fine.

While I would love to ditch all insta-buddies and simply dive with a competent team it's not what I'm able to do on 80-90% of my dives. All I'm looking for is the "best" solution other than ditching insta-buddies. I was hoping to get some input from divers who think with an approach I consider sensible and safe, that's why I asked it in this forum (it's not about the DIR answer, but rather the opinion of DIR divers), instead I've essentially been advised to take the question elsewhere.

While I'm not 100% DIR (not sure anybody is actually), the base concept of "stacking the deck in your favor before the dive ever starts" is valid anywhere.

When diving with one of my regular buddies, there simply isn't a need for a pony bottle. It's just extra crap to get in the way, and when diving with a random stranger, it's probably not enough extra safety to handle the problems.

I was exactly in your shoes a couple of years ago. As TS&M mentioned, the solution is to "grow your own buddy". However I also realize that the world isn't perfect, and sometimes I need to dive with an unknown diver (for example when working as DiveCon on our shop's boat, or on a cruse that my buddy couldn't make). The solution here isn't a pony bottle, it's to plan the dive so it's still safe even if the other diver turns out to be a bozo. This means that I get a lot of 30' dives over the summer, but not only does that make it safer for me, it makes it safer for my insta-buddy in case they decide to "blow and go".

While not the answer you want to hear, the real solution is that if the dive is challenging enough that you feel the need for a pony and don't have a trusted buddy, you might want to pick a different dive.

The real trick to diving safely isn't adding more equipment, it's good planning, good training and good decisions.

Terry

 

[John_B]

I fully get this, but it's similar to this thread: http://www.scubaboard.com/forums/dir/261249-first-stage-flooding-possibly-how-avoid.html, which I posted some time ago where I was looking for input from divers who've already gone down the road I'm traveling. Rather than being ridiculed for my choice of thread placement the question was answered and it actually led to an interesting discussion.

Fair enough.

For a dive like that, wouldn't a set of smaller doubles (AL-80s or LP-85s) suit you better than a single tank and a pony anyway? If redundancy/rock bottom is the problem you are trying to solve, wouldn't doubles with an isolator be a far better solution?