Diving sidemount on liveaboards?

[victorzamora]

I see far more rebreather divers than sidemount divers.

Maybe in your area. I probably see one rebreather diver for every 10 sidemount divers.....and several rebreathers for every doubles diver. I go a long time without seeing a diver with backmounted tanks.

 

[Omisson]

Why do you think/assume I'm complaining? I'm merely pointing out that, from a pure numbers standpoint, sidemount divers comprise a tiny sliver of a sliver of total recreational divers. Not even close to "mainstream" by any reasonable definition. "Sanctioned"? Sure, I'll give you that.

You weren't the one complaining - certain others were. I was making my general point-

 

[SeaCobra]

It is a far superior gear configuration for safety. But you are free to use any approved recreational style you are trained for...

Respectfully, I disagree with this generalization. Now, I do see your points of rationale and agree that sidemount can be a valuable tool, I just do not feel it is the wonder drug that is being touted these days. Your reasons leave out some of the complexities that sidemount creates.

First is the regulator switching. With a manifolded system on my back, my primary goes in my mouth and stays there for the entire time. No need for a switch, except of course if I am moving to a deco gas or air share type of situation. The reg switch also requires a bit of pre-dive planning and it involves a task load during the dive, having to remove one reg, replace it with the other and stow the reg not in use. The reg switch also creates an opportunity for a second stage free flow.

In a manifolded system I only have one pressure gauge to monitor and only one failure point in that regards. Monitor that pressure gauge and stick to the dive schedule accordingly.

You also have potential confusion in the OOA situation. In a manifolded system I am passing you my primary from my mouth and going to my bungeed backup. We all seem to be pretty much in agreement in the tech community on this methodology, I guess there are a few hold outs. In sidemount, first there does not seem to be real uniformity among the training, but the most common I have encountered is to pass the reg with the long hose, which may or may not be in your mouth at the time.

We have to ask ourselves - what problem is being solved? Is that really a problem? And what problems are created by our "solution"?

 

[Dhboner]

First is the regulator switching. With a manifolded system on my back, my primary goes in my mouth and stays there for the entire time. No need for a switch, except of course if i am moving to a deco gas or air share type of situation. The reg switch also requires a bit of pre-dive planning and it involves a task load during the dive, having to remove one reg, replace it with the other and stow the reg not in use. The reg switch also creates an opportunity for a second stage free flow.

On the other hand i know both my regs properly are working at all times. If switching regulators three to four times at the most on a dive is task loading..well. A properly set up and stowed regulator is not a free flow risk even in the great lakes in winter here in toronto.

In a manifolded system i only have one pressure gauge to monitor and only one failure point in that regards. Monitor that pressure gauge and stick to the dive schedule accordingly.

In backmounted doubles in a dir configuration you have to unclip your spg check it and reclip...mine are both right in front of me at all times. I would argue that the manifold actually introduces a failure point.

You also have potential confusion in the ooa situation. In a manifolded system i am passing you my primary from my mouth and going to my bungeed backup. We all seem to be pretty much in agreement in the tech community on this methodology, i guess there are a few hold outs. In sidemount, first there does not seem to be real uniformity among the training, but the most common i have encountered is to pass the reg with the long hose, which may or may not be in your mouth at the time.

I discuss ooa situations with my team before every dive. I can donate the long hose in an instant whether it is in my mouth or not. If it is clipped the bolt snap is on a breakaway clip. There is absolutely no delay.

We have to ask ourselves - what problem is being solved? Is that really a problem? And what problems are created by our "solution"?[/quote]

the problem being solved is the issue that in backmounted doubles i could lose a lot of gas before i successfully identified and shut down the problem post. In sidemount i can see both first stages and tank valves and can respond to a problem pretty much instantly.

 

[SeaCobra]

Again, I ask you, what problem is being solved? How many burst disc failures have happened during a dive? How many tank neck extrusions have happened during a dive? How many regulator failures have happened during a dive? Sure they are dramatic and the get all the press, but how many have actually happened?

As we banter about these scenarios, remember we are talking about the typical diver that hits the water maybe 20 times a year. Not the highly proficient, uber-skilled instructor that we all are .

Yes, you can donate the long hose to an OOA diver whether it is in your mouth or clipped off in an instant. But, as they say, ‘how long a minute is depends on which side of the bathroom door you are on’. For the average diver, donating from the mouth is the consistently fastest way of getting a reg to the OOA diver. Also, since we practice that during our s-drill we establish a level of muscle memory. You say you “discuss” the OOA scenario, do you practice it as part of your s-drill? Do you practice both methods? I do not care how good you are, there will be a time difference in the two methods in the real world.

Speaking of the s-drill, I know my regs are working properly, too, since they were checked by my teammate and myself prior to the dive. During the dive my primary confirms this with every breath and my secondary as well as my lpi works and no surprises on the SPG. I realize a properly stowed reg is not at freeflow risk, that is the same of all bungeed backups. It is the removal of the second stage from the mouth that presents the risk. A freeflowing second stage can dump a lot of gas quicker than you might think. I would prefer to avoid that possibility.

I am not a dir zealot, nor anti-sidemount, I just want to play all the cards face up so people can make an informed decision.

 

[victorzamora]

Again, I ask you, what problem is being solved? How many burst disc failures have happened during a dive? How many tank neck extrusions have happened during a dive? How many regulator failures have happened during a dive? Sure they are dramatic and the get all the press, but how many have actually happened?

How often do people run out of air in a tech scenario? Why train for that at all? Why carry redundant tanks, regs and tanks don't fail too often anyway. Why worry about lost line drills or zero vis drills in a cave? They're SUCH rare occurrences! The point is that any reduction in failure points is welcomed in my book. If it's not welcomed in yours, you need to ask yourself why that is.

Yes, you can donate the long hose to an OOA diver whether it is in your mouth or clipped off in an instant. But, as they say, ‘how long a minute is depends on which side of the bathroom door you are on’. For the average diver, donating from the mouth is the consistently fastest way of getting a reg to the OOA diver. Also, since we practice that during our s-drill we establish a level of muscle memory. You say you “discuss” the OOA scenario, do you practice it as part of your s-drill? Do you practice both methods? I do not care how good you are, there will be a time difference in the two methods in the real world.

Not really. Taking the reg off of a breakaway clip is the same motion as taking it out of my mouth, but six inches to the right. It's the exact same amount of time. Period.

Speaking of the s-drill, I know my regs are working properly, too, since they were checked by my teammate and myself prior to the dive. During the dive my primary confirms this with every breath and my secondary as well as my lpi works and no surprises on the SPG..

No, you know that your backup reg was working sometime in the past. On a big dive, that's HOURS earlier.

It is the removal of the second stage from the mouth that presents the risk. A freeflowing second stage can dump a lot of gas quicker than you might think. I would prefer to avoid that possibility.

If your reg is freeflowing, you should be able to solve it in NO time. Also, I've never had a reg freeflow on my while underwater because I swapped regs out that I can remember. SERIOUSLY not an issue.

 

[Stoo]

I've been diving 40 years, 34 of them packing doubles, and I think I'm about to change to sidemount... for open water diving. My reasons are simple:

(1) I solo dive a lot... the SM configuration is superior for access to valves and stuff
(2) I still have all of the redundancy and capacity advantages that I have with doubles on my back
(3) Previous shoulder injuries (broken + separated) really limit mobility making shutdowns tricky... And I dive in really cold water, where freeze-up is a legitimate risk
(4) I dive from a RIB almost exclusively at home, and hauling twin 130s out of the water is, frankly, continuing to b*gger up my shoulder and back
(5) In spite of what some here are saying, I think SM is going to continue to grow in popularity

With regard to the question of using SM on a liveaboard or charterboat, if damage to the boat and schedules are the issue, then maybe operators need to be clear that those damaging the vessel will be held accountable and insist that they stick to pre-defined 60 minute dive time. SM isn't always about extended range, it's about safety. I am just back from Belize where we did two dives in the Blue Hole. I took a stage kit with me and rigged a spare 80, and for the first time on that dive, I felt properly equipped. I didn't stay much longer than I would have on a single tank, but I had a huge margin of safety, just as I do at home. Doing a 165' dive on a single, borrowed tank is dumb IMHO. I've seen more than one neck o-ring blow in my years of southern diving...

I do share the concern about walking around a rolling deck with dangly gear. The hang-a-tank works well and could easily be accomodated without extra work for the crew.

I will also state that I have never worn a SM rig. In fact, I've only seen one in use, but to me, the advantages and benefits are pretty clear. And frankly the reason I'm probably going to change now is because my wing is worn out, so if I'm going to change, this seems like as good a time as any.

 

[sunnyboy]

I've been diving 40 years, 34 of them packing doubles, and I think I'm about to change to sidemount... for open water diving. My reasons are simple:

...
(2) I still have all of the redundancy and capacity advantages that I have with doubles on my back
(3) Previous shoulder injuries (broken + separated) really limit mobility making shutdowns tricky... And I dive in really cold water, where freeze-up is a legitimate risk
(4) I dive from a RIB almost exclusively at home, and hauling twin 130s out of the water is, frankly, continuing to b*gger up my shoulder and back
...

Funny, these are very similar to the exact reasons why I dumped my twins and went to a rebreather.

I did try sidemount, long enough to work out the kinks. It was fun, but nowhere near as fun as diving my rebreather. Still too gas-limiting for me. It is something I would consider if I had to do more open circuit diving again.

 

[ewaiea]

I guess I shouldn't have cited my Palau trip example a few years ago.....honestly, I really don't care what you guys do with sidemount tanks.....but if I were to ever do something like that I'd clear it with the charter operator. If you want to dive them - feel free. I won't lose any sleep at night.....and again, I'm not complaining about anything - I'm simply taking part in a discussion like everyone else. Some will feel one way - others will feel differently or somewhere in the middle. It's no big deal either way.

I'm going to smoke my peace pipe now.

 

[Shasta_man]

Is that a back mount or sidemount peace pipe?