Pull Dumps — lose them

[aquacat8]

In the event of a stuck inflator, I don't think trying to vent through a pull dump would be as effective as venting through a butt dump and finning down to maintain depth.

FINALLY some one said this! I was mystified thinking why do I think so differently than everyone, am I wrong? Because for me in a runaway ascent there is only one dump that would matter and that would be my butt dump as I would have my butt up as I was madly finning down. I might have to take my hand off briefly to disconnect, but I’d still be finning down!

 

[aquacat8]

I have also seen a diver prefer oral inflate...

 

[Colliam7]

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MOD POST

The posts previously made after #213 generally concerned a topic separate and distinct from the discussion of Pull Dumps. Those posts have been moved to a new thread, discussing Cylinder Type and Proper Weighting (Cylinder type and proper weighting)

Please continue to post in this thread your comments regarding pull dumps, inflators, etc.
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[rongoodman]

FINALLY some one said this! I was mystified thinking why do I think so differently than everyone, am I wrong? Because for me in a runaway ascent there is only one dump that would matter and that would be my butt dump as I would have my butt up as I was madly finning down. I might have to take my hand off briefly to disconnect, but I’d still be finning down!

It's even simpler with doubles. Open the rear dump and shut down the right post while finning down. You can then disconnect the hose at your leisure.

 

[Steelyeyes]

FINALLY some one said this! I was mystified thinking why do I think so differently than everyone, am I wrong? Because for me in a runaway ascent there is only one dump that would matter and that would be my butt dump as I would have my butt up as I was madly finning down. I might have to take my hand off briefly to disconnect, but I’d still be finning down!

It's very effective. I had an incident where a too short operating cable for my pull dump caused it to open when I would lift up my inflator to add air. Zero air went in the bladder. Luckily I was in a dry suit so I was able to get neutral and figure out the issue. If you look at the construction of the pull dump valve, at least on my Zeagle BCDs, it's higher than the bladder when you're horizontal and vertical since it's the top of the 90 degree elbow.

In a head down, finning, and venting from the bottom dump scenario you have get air into the bladder to then let it out again. Not an optimum situation.

Reacting to a stuck inflator with a pull dump requires zero change in body position and most likely won't cause a runaway ascent. You already have the pull dump actuator in your hand when you press the inflator button. If it sticks just pull the hose and keep it that way until you can get the inflator disconnected.

 

[northernone]

I have also seen a diver prefer oral inflate...

Yes. This one certainly does. Particularly on dives where a positive buoyant ascent would be undesirable. When I have a power inflator I have it pinned to reduce flow.

...I do have detachable weight though if I needed to float to the surface.

To wade into this discussion. I'm not sure blaming the equipment is an adequate lesson to be learned from an incident where an an instructor who, in a moment of panic, did not have the skill needed to respond to his situation and did not have a buddy near by enough to prevent him from "nearly drowning"

 

[Steelyeyes]

Yes. This one certainly does. Particularly on dives where a positive buoyant ascent would be undesirable. When I have a power inflator I have it pinned to reduce flow.

...I do have detachable weight though if I needed to float to the surface.

To wade into this discussion. I'm not sure blaming the equipment is an adequate lesson to be learned from an incident where an an instructor who, in a moment of panic, did not have the skill needed to respond to his situation and did not have a buddy near by enough to prevent him from "nearly drowning"

I agree.

 

[Diving Dubai]

To wade into this discussion. I'm not sure blaming the equipment is an adequate lesson to be learned from an incident where an an instructor who, in a moment of panic, did not have the skill needed to respond to his situation and did not have a buddy near by enough to prevent him from "nearly drowning"

Yes, it's really easy to find fault with someone based upon their certification level. Indeed I was particularly dismayed that some, here were "baying for blood" early on.

The reality is, no-one can be sure how they'll react in when for them at least, it's all going wrong, and a degree of panic and terror takes hold.

I've had a few shall we say, sticky situations. I choose to dive in "challenging" conditions and mother nature bites back. I know how I will act under pressure and stress especially when I know if I don't get it right then that's going to be the end.

I'm still here. But after each and every incident there has never been a time that with hindsight that I haven't thought that I could not have done better.

If people glibly think it's couldn't happen to them, well there's on thread a few years ago where a highly respected and incredibly experienced SB staff member perished in 12' of water.

It's the silly things that will get you every time.

 

[northernone]

Yes, it's really easy to find fault with someone based upon their certification level. Indeed I was particularly dismayed that some, here were "baying for blood" early on.

The reality is, no-one can be sure how they'll react in when for them at least, it's all going wrong, and a degree of panic and terror takes hold.

I've had a few shall we say, sticky situations. I choose to dive in "challenging" conditions and mother nature bites back. I know how I will act under pressure and stress especially when I know if I don't get it right then that's going to be the end.

I'm still here. But after each and every incident there has never been a time that with hindsight that I haven't thought that I could not have done better.

If people glibly think it's couldn't happen to them, well there's on thread a few years ago where a highly respected and incredibly experienced SB staff member perished in 12' of water.

It's the silly things that will get you every time.

True. Even a teaspoon of water in the wrong place at the wrong time can ignite horror.

 

[Steelyeyes]

Sometimes you just have a brain fart. I was on a dive a bit over a year ago and one of the other divers, who had over 200 logged dives, somehow forgot to vent his BCD completely when it was time for the initial descent of the day. He was head down and kicking at about 15 feet as the rest of us floated down. The DM saw it, made sure the rest of us were OK and went up to straighten him out. He had no issues for the rest of the day. Good thing it was something non life threatening.