Safe Second Inflators vs Octopus Regs

[blawler1]

For the record the Sidekick is a inline octo, not an integrated model like the Air II so there are no issues regarding inhaling BC air through the Sidekick at any time.

I used to use a full octopus, but it was more trouble than it was worth as it had to be stowed, and was subject to free flows. The placement of the octo was problematic for using a DPV as the vortex will often generate free flows unless you use a cap or bulb over the octo mouthpiece. I switched to the Sidekick to streamline my setup and to some extent it did. It does add weight to the inflator, but you do lose a hose. I even had instance when it came in particularly handy when my wife kicked my regulator out of my mouth and I was quickly put the Sidekick in my mouth. Additionally, I think any discussion regarding whether you can breath off the Sidekick and operate your dump valves/maintain buoyancy control is a non issue.

I have recently switched to an inflator hose mounted Air Buddy, the focus of much skepticism on this board, but thats OK because it works for me and only weights a few ounces more than no octo at all.

 

[Adobo]

For the record the Sidekick is a inline octo, not an integrated model like the Air II so there are no issues regarding inhaling BC air through the Sidekick at any time.

I think it is the same with Zeagle's Octo+. However, in general, like you say, AIR2 type of systems and their clones do have that behavior. Whether or not it is an issue is a different thing altogether.

I used to use a full octopus, but it was more trouble than it was worth as it had to be stowed, and was subject to free flows. The placement of the octo was problematic for using a DPV as the vortex will often generate free flows unless you use a cap or bulb over the octo mouthpiece.

Yet another reason not to stow a backup regulator on a clip.

Just to be clear though, you're describing your experience with an octo clipped somewhere on your torso. You're not describing a problem you had having it on a bungy hung from your neck, correct? The dozens of divers I see with this configuration on a regular basis, non are complaining of free flowing backup second stages. And of the 10 or so divers that I know who use scooters on a regular basis, this hasn't been an issue I've heard of.

A video of two divers with scooters is available on the link below. Both of them have backup second stages on bungies without any sort of cap to cover the mouth piece.

http://www.dive-xtras.com/scooter/video/ptlobos.html

 

[daniel f aleman]

Completely off topic but I was in Cozumel last year diving my standard singles rig (bp/wing, 7' primary, bungied secondary). A couple of newbies came up to me and my similarly outfitted buddy as asked us if we just got certified. Our response was "huh??". They said well why don't you use a integrated inflator/secondary. We laughed.

I wouldn't consider you newbies, of course, just wannabes.

 

[loosebits]

I wouldn't consider you newbies, of course, just wannabes.

Yep, I definitely wannabe

Doing full cave with adv nitrox/deco in FL in a few days and heading down to Akumal in July for a week down there.

 

[Mandy3206]

I think it is the same with Zeagle's Octo+. However, in general, like you say, AIR2 type of systems and their clones do have that behavior. Whether or not it is an issue is a different thing altogether.

Not sure what you mean by this, but if you mean that the Zeagle Octo+ is an inline design, this isn't correct, the Zeagle Octo+ is an integrated octo/inflator similar to Air II but in a diferent configuration.

IMO, the Air II design is better than the Octo+ since the ergonomics are better and easier to use on the Air II or clones (Tusa Duo Air)

 

[Adobo]

Not sure what you mean by this, but if you mean that the Zeagle Octo+ is an inline design, this isn't correct, the Zeagle Octo+ is an integrated octo/inflator similar to Air II but in a diferent configuration.

The same in that inhaling from an Octo+ while using it to purge gas from your BC does not cause gas from the BC to be inhaled.

 

[Mandy3206]

The same in that inhaling from an Octo+ while using it to purge gas from your BC does not cause gas from the BC to be inhaled.

Nope, wrong too, the Zeagle Octo+ is similar to Air II design in the aspect that vented gas uses the same chamber used for breathing gas.

IMO a small amount of gas from the bladder will not harm anyone, I suck dry my bladder every time before putting it back in the dive bag (in my case, a Pelican 1620 case) so the bladder is easier to pack, for storage, I let a small amount of air in the bladder and hang the dry BC in the UK BC hanger in my gear room.

 

[Adobo]

Nope, wrong too, the Zeagle Octo+ is similar to Air II design in the aspect that vented gas uses the same chamber used for breathing gas.

Go argue it with Larry at Scubatoys and Jim Fox at Zeagle...

IMO a small amount of gas from the bladder will not harm anyone, I suck dry my bladder every time before putting it back in the dive bag (in my case, a Pelican 1620 case) so the bladder is easier to pack, for storage, I let a small amount of air in the bladder and hang the dry BC in the UK BC hanger in my gear room.

In your opinion it is not harmful. In the opinion of other people it is. Who is right, who is wrong? Don't know, don't care. Those doo-hickeys vents air from the BC which you wind up inhaling when you use them. Just stating the facts.

 

[bperrybap]

IMO a small amount of gas from the bladder will not harm anyone, I suck dry my bladder every time before putting it back in the dive bag (in my case, a Pelican 1620 case) so the bladder is easier to pack, for storage, I let a small amount of air in the bladder and hang the dry BC in the UK BC hanger in my gear room.

The issue that I'd be concerned about isn't the accidental breathing of a
small amount of gas from the bladder but the inability to vent and overfilling
your lungs causing pulmonary barotrauma.

This is only an issue in fully integrated octo+ units.
(Not units like shadow+, sidekick etc... those won't have this issue)

In fully integrated octo+ type devices, there is only a single mouth piece
and the the vent function/button works two ways
depending on how far or how hard you press the button. If you depress
the button half way, air from the BC bladder is routed out to the mouth
piece but air can still escape from the regulator exhaust.
If you fully depress the vent button, air from the BC bladder is routed ONLY
to the mouth piece. Air paths between the mouth piece and the 1st stage and
the 2nd stage exhaust are completely blocked. The mouth piece is fully
and directly connected to the BC air bladder.
This is done to allow manually filling the BC using the same mouth piece
as for breathing from the 2nd stage.

Sounds Ok and simple right?

Well, in a OOA donation situation all kinds of unpredictable things start to happen.
Things can be complicated because of using a "standard" length
primary or a paniced diver.

Now if during all this stress, you find youself needing to vent quickly because
you are rising too quickly, you will immediately press the vent button.
However, assuming the octo+ mouthpiece is still in your mouth and
if you press the vent button too hard, nothing will vent (because the
air bladder is connected directly to your mouth piece) or even worse,
the BC will want to vent all the excess pressure directly into your lungs rather
than out into the water.
If you start to get confused and continue to hold the button down and press
harder without releasing, the situation will persist. You WILL be able to take breaths in but
will be unable to breath out because the excess pressure in the BC air bladder
will be stronger than your diaphram can push. Unless you let go of the
vent button, pull the shoulder dump/vent, or remove the mouth piece,
you face the possibility of lung injury not to mention that you are probably
ascending way to fast by this point which could cause other problems.

My feeling is that the ability to breath in yet not breath out or vent all while
starting to rise quickly will potentially panic the diver and the ensuing panic
will cause the diver to push even harder on the vent button just like people in
cars that had "run away acceleration" by confusing the gas pedal with the
brake tended to push the gas pedal even harder as they became paniced
which just made the situation worse.

So you are probably wondering how would I know this or predict this?

Well, this is what happend to me the first time I used my octo+ in a pool
during training. It was very awkward and I wasn't yet familiar with
the proper venting techniques of the octo+ or the sharing procedures
involved for this type of equipment.
(Let's just say that there is a big difference between understanding the
theory of the device and air sharing and actually being able to do it)

I did manage spit the octo+ regulator out of my mouth so
luckliy no injury just a very awkward situation. Both my wife and I
ended up swallowing a bit of pool water.

So even after that pretty frightening initial experience. I still have and use
my Atomic SS1. After some practice with it, I don't think it's a big deal
to use it. I do like it and I don't really see a problem with using octo+ type of
devices in non overhead, openwater
rec type diving. Also, my wife (dive buddy) doesn't have a problem with and
is comfortable with the sharing of air while I'm using it.

However, I would highly recommend to anyone that uses or plans on using a
integrated octo+ to practice with it, especially venting.
For me, I always vent with the octo+ out of my mouth.

--- bill

 

[Mandy3206]

The issue that I'd be concerned about isn't the accidental breathing of a
small amount of gas from the bladder but the inability to vent and overfilling
your lungs causing pulmonary barotrauma.

This is only an issue in fully integrated octo+ units.
(Not units like shadow+, sidekick etc... those won't have this issue)

In fully integrated octo+ type devices, there is only a single mouth piece
and the the vent function/button works two ways
depending on how far or how hard you press the button. If you depress
the button half way, air from the BC bladder is routed out to the mouth
piece but air can still escape from the regulator exhaust.
If you fully depress the vent button, air from the BC bladder is routed ONLY
to the mouth piece. Air paths between the mouth piece and the 1st stage and
the 2nd stage exhaust are completely blocked. The mouth piece is fully
and directly connected to the BC air bladder.
This is done to allow manually filling the BC using the same mouth piece
as for breathing from the 2nd stage.

Sounds Ok and simple right?

Well, in a OOA donation situation all kinds of unpredictable things start to happen.
Things can be complicated because of using a "standard" length
primary or a paniced diver.

Now if during all this stress, you find youself needing to vent quickly because
you are rising too quickly, you will immediately press the vent button.
However, assuming the octo+ mouthpiece is still in your mouth and
if you press the vent button too hard, nothing will vent (because the
air bladder is connected directly to your mouth piece) or even worse,
the BC will want to vent all the excess pressure directly into your lungs rather
than out into the water.
If you start to get confused and continue to hold the button down and press
harder without releasing, the situation will persist. You WILL be able to take breaths in but
will be unable to breath out because the excess pressure in the BC air bladder
will be stronger than your diaphram can push. Unless you let go of the
vent button, pull the shoulder dump/vent, or remove the mouth piece,
you face the possibility of lung injury not to mention that you are probably
ascending way to fast by this point which could cause other problems.

My feeling is that the ability to breath in yet not breath out or vent all while
starting to rise quickly will potentially panic the diver and the ensuing panic
will cause the diver to push even harder on the vent button just like people in
cars that had "run away acceleration" by confusing the gas pedal with the
brake tended to push the gas pedal even harder as they became paniced
which just made the situation worse.

So you are probably wondering how would I know this or predict this?

Well, this is what happend to me the first time I used my octo+ in a pool
during training. It was very awkward and I wasn't yet familiar with
the proper venting techniques of the octo+ or the sharing procedures
involved for this type of equipment.
(Let's just say that there is a big difference between understanding the
theory of the device and air sharing and actually being able to do it)

I did manage spit the octo+ regulator out of my mouth so
luckliy no injury just a very awkward situation. Both my wife and I
ended up swallowing a bit of pool water.

So even after that pretty frightening initial experience. I still have and use
my Atomic SS1. After some practice with it, I don't think it's a big deal
to use it. I do like it and I don't really see a problem with using octo+ type of
devices in non overhead, openwater
rec type diving. Also, my wife (dive buddy) doesn't have a problem with and
is comfortable with the sharing of air while I'm using it.

However, I would highly recommend to anyone that uses or plans on using a
integrated octo+ to practice with it, especially venting.
For me, I always vent with the octo+ out of my mouth.

--- bill

Very informative post, thanks