Great lesson for Newbies and Veterans alike!

[RJP]

I think you meant never remove a working regulator?

You think wrong.

 

[Storker]

You think wrong.

Care to elaborate?

 

[RJP]

Removing when then? When already holding the donated reg?

Not even then. Not until the donated reg is also properly oriented.

Don't ever remove a non-working regulator from your mouth until you are ready to replace it with something better.

Period.

Why?

If an OOG diver tries to take a breath with a reg in their mouth they will get nothing.
If an OOG diver tries to take a breath with NOTHING in their mouth they will get WATER.

This is why we don't teach (or even allow) students to spit the reg during a CESA. In a training setting, you want them to be able to get a breath if they need to. In a real situation you don't want them filling their lungs with water.

Plus... as a truly OOG diver ascends, and ambient pressure decreases, they might actually get a breath or two out of their tank as they approach the surface. But only if they still have their regulator in their mouth.

 

[Redshift]

I understand the logic behind that during CESA, but to ask for air and actually take another reg, one has to spit the non-working (or working if in exercise) reg out. So that rule of "never" is not applied in such situation.

 

[RJP]

I understand the logic behind that during CESA, but to ask for air and actually take another reg, one has to spit the non-working (or working if in exercise) reg out. So that rule of "never" is not applied in such situation.

Read more carefully...

Never remove a non-working regulator from your mouth until you are ready to replace it with something better.

There's also no reason to "spit the reg" one way or the other; it can simply be "removed."

 

[TSandM]

How do you fill an SMB while sharing gas? The same way you do when you aren't . . . you take the reg you are breathing out of your mouth and inflate the bag, then return the reg to your mouth.

I do agree that one shouldn't spit the reg out while drilling, and in fact, GUE has changed that procedure, and I was scolded for doing so during my recent Fundies redo.

 

[Akimbo]

Not even then. Not until the donated reg is also properly oriented.

Don't ever remove a non-working regulator from your mouth until you are ready to replace it with something better.

Period....

There is a serious underlying problem if you can’t trust the divers you are training to take the regulator out of their mouth under any circumstances and not inhale water.

 

[RJP]

There is a serious underlying problem if you can’t trust the divers you are training to take the regulator out of their mouth under any circumstances and not inhale water.

"Trust... but verify."



But seriously, it's not a matter of trust. It's a matter of avoiding a practice (reflexively removing a non-working/OOG reg prior to securing a working one) that has ZERO upside and - however remote the likelihood of occurrence - nothing but grave potential on the downside.

 

[Akimbo]

… It's a matter of avoiding a practice (reflexively removing a non-working/OOG reg prior to securing a working one) that has ZERO upside and - however remote the likelihood of occurrence - nothing but grave potential on the downside.

That is a pretty specific circumstance compared to:

… Don't ever remove a non-working regulator from your mouth until you are ready to replace it with something better.

Period...

The gravest potential downside is an air embolism during a free ascent or CESA, not depleting Oxygen in the body. More specifically, panic or ignorance that causes a diver to close their airway during and emergency ascent.

It is harder to keep your airway open when biting a mouthpiece, especially in a high-drama situation. This was pointed out to me by a Navy Diving instructor who recently transferred from being an instructor at the submarine escape tower in New London. It is hard to imagine any job more experienced at preventing air embolism than that.

As explained to me, that is one of the reasons the Steinke hood replaced the Momsen lung for submarine escape in the US. He walked me through a few exercises of keeping the airway open and it demonstrated to me that he was right.

One factor working against keeping your airway open with a mouthpiece is the natural tendency to bite down harder in an emergency, which tenses up muscles that close the airway. The other is the reflex to swallow tiny amounts of water in the mouthpiece when you are in the head-up position to keep your airway open. Swallowing causes a momentary closing of the airway. The Mammalian diving reflex is pretty effective at preventing inhaling water without a mouthpiece. That is the main reason that freedivers are taught to spit the snorkel out immediately after leaving the surface.

It is difficult to create enough backpressure in the lungs by closing your lips alone to cause damage. Closing the airway at the base of the tongue is another matter and is what causes the great majority of air embolisms in diving.

I’m not suggesting that CESAs are a poor choice given the very limited training schedules available, but your absolute statement above is flawed. Divers will soon gain enough experience to know that removing their regulator for different reasons is not dangerous and that can lead to questioning everything they learn from you.

Here is an old video on submarine escape training or anyone interested:

[video=youtube;ffOJEJwWSbs]https://www.youtube.com/watch?v=ffOJEJwWSbs[/video]

 

[pedo]

How do you fill an SMB while sharing gas? The same way you do when you aren't . . . you take the reg you are breathing out of your mouth and inflate the bag, then return the reg to your mouth.

I do agree that one shouldn't spit the reg out while drilling, and in fact, GUE has changed that procedure, and I was scolded for doing so during my recent Fundies redo.

Don't ever remove a non-working regulator from your mouth until you are ready to replace it with something better.

You can't fill a bag from a non-working reg.