Has anyone had a “free flowing” nose on a rebreather?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

The description sounds very similar to what some folks experience with the positive pressure flow of cpap machines.

-Z
 
I've had it happen after several hours on OC, I don't remember it happening on CCR though. I always assumed it was soft palate fatigue, since once it starts, it doesn't really stop for me. Actually I can take my mask off for a bit, and it goes away once I put it back on. A little rest goes a long way it seems.
 
I've had it happen after several hours on OC, I don't remember it happening on CCR though. I always assumed it was soft palate fatigue, since once it starts, it doesn't really stop for me. Actually I can take my mask off for a bit, and it goes away once I put it back on. A little rest goes a long way it seems.
The more I research this, the more I believe you are correct -- it seems to be a soft palatal air leak (also called Stress Velopharyngeal Insufficiency). This seems to be an issue with some musicians who play wind instruments. I didn't think to take my mask off when it started...I may try that next time it happens.

An interesting article on it I found if anyone is interested.
 
First time: Happened to me on a KISS SideWinder after an extended period of semi closed breathing during initial crossover training with Edd. Upon ascent I could not stop exhaling through my nose and had to hold my mask on to keep loop volume. I ended up bailing out and sitting still for a while before getting back on the loop.

Second time: Happened while ascending also and it was helped by maintaining horizontal trim position. This was on the SW again.

Never happened on any other unit. I have about 500 hours total on CCRs. All back mount CLs.

The snorting happens sometimes at or close to Min Loop Vol. I try and keep the loop slightly above MLV and don't usually have a problem even on longer two to three hour trimix dives.
 
What are we going to call this "new" phenomenon?

"Post Nasal Draft"?
"Nasal Nortle"?
"Soft Palate Prostration"?

That's all I've got for now...
 
The last time I used a rebreather, my nose was blocked and I had a bad case of the flu. Try venting gas through your lips instead.
Easier said than done. Depends upon the mouthpiece and if there’s a gag strap. Runs a risk of letting water in the loop and easiest to do if not horizontal, so there’s some gas pressure.
 
I experienced this, too. Felt a bit like snorting, like already mentioned. Using a JJ with DSV, gas is usually Trimix with a quite high He fraction. E.g. 15/55 for a 30m dive.
It often happend when I had to "work" a bit heavier (taking pictures) or when a bit excited. CO2 can be a contributing factor. Happend quite early in the dive, got better when concentrated on stop "working" and during deco.
Don't want to be rude, but it maybe is related to weight / fitness regime. I tend to snort when sleeping. Reducing my weight improves at least the snorting...
 
I experienced this, too. Felt a bit like snorting, like already mentioned. Using a JJ with DSV, gas is usually Trimix with a quite high He fraction. E.g. 15/55 for a 30m dive.
It often happend when I had to "work" a bit heavier (taking pictures) or when a bit excited. CO2 can be a contributing factor. Happend quite early in the dive, got better when concentrated on stop "working" and during deco.
Don't want to be rude, but it maybe is related to weight / fitness regime. I tend to snort when sleeping. Reducing my weight improves at least the snorting...
How did/does it stop when you experience this?

For me, it seems to go away once I ignore it! It happens occasionally, but only once during a dive.

Not noticed it on deeper dives, >60m/200ft. Have noticed it in shallower dives.
 

Back
Top Bottom