Water in regulator at depth causing panic

[berndo]

... but you do need to have solid skills if you're in a hard or soft overhead environment with mixed gases; ...

Apparently you haven't been around the block much than. There are plenty of people that dive caves and don't have solid skills.

It's funny how you put stuff in bolt but ignore the 'I've seen/I see' that's right before what you put in bolt.

Assume this was once, or was it in a specific location that some DiveMasters took people beyond the cavern zone?

Don't assume/make stuff up. Just read what I wrote.

 

[Wibble]

Apparently you haven't been around the block much than. There are plenty of people that dive caves and don't have solid skills.

It's funny how you put stuff in bolt but ignore the 'I've seen/I see' that's right before what you put in bolt.


Don't assume/make stuff up. Just read what I wrote.

Crap.

 

[berndo]

Well, you focus mostly on the mask keeping tanks with both arms, then you expell the gas from the lungs upon ascend.

Usually you're supposed to hold the mask with your fingers and use the palm of the same hand to hold the reg in place.

 

[inquis]

Or is this effect somehow negated by the drop of PPCO2 as you ascend?

Bingo. The PCO2 gradient drives the diffusion of molecules from the blood into the alveoli. There are two competing drivers that want to change the rate at which CO2 is removed: Ascent/exhalation wants to lower the PCO2 in the lungs, increasing the removal rate of CO2 from the blood. Diffusion from blood wants to slow the removal rate. As long as the net removal rate in the lungs is greater than the rate CO2 enters the blood from the tissues (after metabolism), the concentration (in the blood reaching the brain) doesn't increase. Until the concentration rises sufficiently, the brain won't insist you take a breath.

 

[steinbil]

Bingo. The PCO2 gradient drives the diffusion of molecules from the blood into the alveoli. There are two competing drivers that want to change the rate at which CO2 is removed: Ascent/exhalation wants to lower the PCO2 in the lungs, increasing the removal rate of CO2 from the blood. Diffusion from blood wants to slow the removal rate. As long as the net removal rate in the lungs is greater than the rate CO2 enters the blood from the tissues (after metabolism), the concentration (in the blood reaching the brain) doesn't increase. Until the concentration rises sufficiently, the brain won't insist you take a breath.

Good to know. Thanks for the explanation.

 

[lowwall]

Well, you focus mostly on the mask keeping tanks with both arms, then you expell the gas from the lungs upon ascend. At that time the reg was gone. Maybe I was sloppy or it happened when the reg was released from the hand on the way up. Not sure, but interesting point. Will focus on that subject when jumping next time to understand at which moment the reg flown away. Thanks for the notice.

? Maybe a sidemount thing?

Normal rec procedure when entering water is palm/heel of hand over reg and fingers over mask. This is from The Easy In: Tips for Performing the Giant Stride Entry - Dive Training Magazine | Scuba Diving Skills, Gear, Education

 

[Salt]

I

As people have tried to explain, if the regulator "fixed itself" while underwater, this does not mean that there was necessarily a failure to maintain the regulator. It is up to YOU, to try to inhale from the regulator BEFORE it is pressurized and ensure that the integrity of the second stage is in tact and there are no (or negligible) leaks when you suck a gentle vacuum.

I know everyone wants to pat you on the back for not bolting to the surface and handling the problem at 60 feet, but the reality is that you need to check this stuff on any regulator before jumping in. Even over zealous rinsing of regulator can cause an exhaust valve to get folded a little or it can happen in rare instances when jumping into the water and water slamming into the exhaust.

I wonder if many people actually do the vacuum test before diving, I generally do it every time I load the regulators into the gear bag (the night before) and sometimes do it on the boat- but it should be done every time before a dive - even on brand new regulators.

I don’t believe I was ever shown this in any of my training.

Frankly, I don’t understand this bit or the mechanics of the regulator itself. I’ll do a little research and see what I can figure out.

Basically, it’s been: breathe here, make sure air is coming out, and know how to switch to your backup or your buddy’s backup if it stops working.

 

[Salt]

Yes, the vacuum test is different. Inhalation against a closed valve should create a vacuum, which confirms your diaphragm and exhaust diaphragm are functioning properly, that the regulator housing is intact, and that your mouthpiece is attached and in sound condition. If you inhale and get air, it is likely one (or both) of your diaphragms is either not seated properly (folded, has sand between it and the regulator housing, et cetera), or has a hole or tear. It could also be that your mouthpiece isn't properly secured or has a hole, or that your regulator has a crack.

The vacuum test before the dive essentially verifies that when you inhale from your regulator underwater, you will get the expected lungful of gas, rather than water.

Thank you for the clarification

 

[boulderjohn]

Until the concentration rises sufficiently, the brain won't insist you take a breath.

Correct.

In addition, let's say the diver did feel a need to inhale. What happens?

• If the diver is still exhaling because of the expanding gas in the lungs, the diver cannot inhale.
• If the lungs have emptied enough to make inhalation possible, the diver will be attempting to inhale through a regulator still properly placed in the mouth. Water will not be inhaled.
• When the diver attempts to inhale through that regulator, the diver will probably be successful, because by then the decrease in ambient pressure will allow the regulator to provide the needed air.

 

[johndiver999]

It has

I


I don’t believe I was ever shown this in any of my training.

Frankly, I don’t understand this bit or the mechanics of the regulator itself. I’ll do a little research and see what I can figure out.

Basically, it’s been: breathe here, make sure air is coming out, and know how to switch to your backup or your buddy’s backup if it stops working.

Maybe get someone to disassemble a second for you and try to imagine how it works on the most rudimentary basis? You only need a superficial understanding of the design, to understand exactly what the vacuum test is, it will be very beneficial, you might be surprised how thin of a diaphragm is between you and downing.