inhale from reg exhale from nose

[ezadel]

That in turn inhibits CO2 elimination which exacerbates almost all hyperbaric maladies

interesting thought could you explain further why not clearing all the CO2 causes this ?

. If that doesn’t kill you mask fogging will annoy the devil out of you.

never had a problem with that in warm or cold water

 

[Diver0001]

Hello,
I wanted to get your opinion. Is it a bad habit to inhale from reg and breath out through nose. I have one of the cheap masks with a purge valve, and found that doing that automatically clears my mask, produces much less interference feom the bubbles as they do not obstruct my vison..what do you think?

I don't think it matters much either way. I do what you're talking about sometimes in the winter because the warm air that I exhale goes into the cap and keeps me a tiny bit warmer.

R..

 

[CuzzA]

interesting thought could you explain further why not clearing all the CO2 causes this ?

never had a problem with that in warm or cold water

This should get you started...

Hypercapnia - Wikipedia

Failure to adequately eliminate CO2[edit]
There is a variety of reasons for carbon dioxide not being expelled completely when the diver exhales:

• The diver is exhaling into a vessel that does not allow all the CO2 to escape to the environment, such as a long snorkel, full face diving mask, or diving helmet, and the diver then re-inhales from that vessel, causing increased dead space.[14]

*While not the exact definition of what could happen in your situation, the concept is similar to what Akimbo mentioned. It's possible by exhaling through your nose and through the purge valve that you are not fully ventilating your lungs and removing co2. The consequences of this depend on depth, co2 retention and a number of factors that could lead to nothing, a headache or worse.

 

[Akimbo]

interesting thought could you explain further why not clearing all the CO2 causes this ?...

Wow, that is a HUGE question that is best for the left for the Marine Science and Physiology forum! The brief summary of the Reader's Digest version is elevated CO2 lowers your resistance to IGN (Inert Gas Narcosis), Oxygen Toxicity, panic, and peak exertion levels.

 

[CuzzA]

In other words, co2 is the devil in diving.

 

[Akimbo]

In other words, co2 is the devil in diving.

More like too much of a good thing is bad. You need enough CO2 to stimulate breathing but not much more. Is there a goldilocks icon?

 

[KeithG]

Wow, that is a HUGE question that is best for the left for the Marine Science and Physiology forum! The brief summary of the Reader's Digest version is elevated CO2 lowers your resistance to IGN (Inert Gas Narcosis), Oxygen Toxicity, panic, and peak exertion levels.

i think the actual question is: why do you think exhaling into a mask increases co2 retention?

i randomly exhale through my mouth or nose. i have not noticed any difference.

 

[ezadel]

i think the actual question is: why do you think exhaling into a mask increases co2 retention?

I think his idea is maybe because the purge valve is small it will encourage shallow breathing and thus increase pp co2 eventually. this might be true however , i dont feel any extra exertion when i do it in fact, to me it feels more natural/comfortable but this maybe due to humans being used to breathing in/out through nose

 

[Hou s4m]

I was exhaling thru my nose during my earlier dives. Also got something to do with needing to clear my mask constantly at the time. I was still getting use to scuba then. I think the warm air irritates my eye somehow that i could barely open it the next day. That was a lesson for me.

 

[Akimbo]

i think the actual question is: why do you think exhaling into a mask increases co2 retention?....

Exhalation resistance and therefore the total work of breathing increases when you exhale through a small purge valve on a mask.

Too loud?

... i randomly exhale through my mouth or nose. i have not noticed any difference.

Define randomly. Burping a few bubbles out of your mask or a full lung exhalation? A few bubbles slowly expelled has no effect. Exhaling at a normal rate under a light to moderate workload will build up backpressure and release air past the skirt of the mask. Humans aren't sensitive enough to detect increased breathing resistance unless they are under heavy workloads. But the effect of prolonged higher WOB (Work Of Breathing) is easily measured in blood CO2 levels.

This is not a stupid rule like never "hold your breath". More like normally exhaling through your nose is like using a really bad regulator in disrepair from the 1950s.