Best CCR in 2025-2030 Rebreather Markets

[flymolo]

you're saying do all this after water has passed through the unit and scrubber and made it all the way to the inhale side of the loop?

 

[mr_v]

you're saying do all this after water has passed through the unit and scrubber and made it all the way to the inhale side of the loop?

No, you missed the fine details. That's why teaching CC diving and emergency procedures should not be done on internet forums. You do not want to drink caustic cocktail - it is a chemical burn that will do serious damage and may lead to a fatality.

On a rEvo, you may have non-caustic flood scenarios where water enters a lung without going through sorb.

Exhale lung flood. Causes: loose lips, emergency drills, forgot to close DSV, bad OPV, loop compromised on the exhale side. If you flood the exhale lung, you turn in the dive, stay horizontal so that the water does not travel into the sorb resulting in casutic cocktail.

Inhale lung flood. Causes: compromised loop on the inhale side. You may also get a lot of condensation after swimming for hours. The excessive condensation is not a flood and there won't be enough of it to cause any serious concern. In either case, you can either force the water to the exhale lung and keep it there or "drink and spit it out."

The second approach requires knowing what caustic tastes like and the ability to distinguish it from other substances, like steramine that has remained in the loop after sanitization. The best way to experience that taste is intentional - create a small caustic cocktail mix and taste it with the tip of your tongue. Do the same for steramine. Some of you may think it is crazy, but it is crazier to think that it will tingle like a 9V battery - it won't, and you'll have a significant emotional event.

I am sure some of you will reply finding holes in the logic above. That's why I'd like you to re-read the first paragraph. SB is not where you learn CC diving.

When in doubt, bail out.

 

[flymolo]

How does water get into the inhale side?

 

[211ratsbud]

How does water get into the inhale side?

Happened to me several times.

In my case I had a malfunctioning bayonet on my bov

 

[mr_v]

How does water get into the inhale side?

Anything that compromises the loop on the inhale side. By "loop" I mean the entire inhale system. E.g., DSV/BOV connectors, the bulkhead (sensor cables), the actual loop (like holes in the loop) or the loop-to-case attachment points.

 

[Wibble]

you're saying do all this after water has passed through the unit and scrubber and made it all the way to the inhale side of the loop?

Not on a Revo — unless you do a barrel roll!

The water from loose lips/not tightening up the DSV hose clips will pass into the smaller exhale lung. Actually it’ll pool on the outside of the exhale mushroom and bubble a lot and eventually bubbles back into the mouthpiece.

The standard loop clearing procedure on a Revo is to do the “Hero” move: vertical-ish trim, take mouthpiece out (sealing the DSV as normal) and shake the water out of the loop, down into the exhale lung; mouthpiece back in mouth. This works OK unless you go into fully flat trim or head down when the water will flow out of the exhale lung back into the exhale side of the loop and it’ll start bubbling again. So repeat and don’t go head down.

If you have some water in the exhale loop and need to go head down for some passage/geology/wreck it might be worth while coming off the loop for a while until you can get into a more head-up trim, getting back on the loop and clearing it using the hero move.


The biggest thing is to deal with water in the loop and ensure there’s no other leak. The dumbass mistake is to have the DSV partially open which lets water into the loop. You only do this once and learn from your mistakes.

I guess a Revo is perfectly OK with, say, a cupful of water in the exhale loop as long as you:

• Do not go flat or head down as it’ll flood the exhale mushroom
• Do not go vertical as you’ll pour the liquid through the exhale scrubber, over the gap and into the inhale scrubber. This is where you’ve now caused a caustic cocktail.

Mostly it’s just lung butter (condensed breath that’s liquified) following a long dive in colder water. By stashing a rolled half-cloth in the exhale lung behind the hoses this will absorb a desert spoonful of liquid without it pouring back down the exhale loop — this isn’t Revo approved, but many Revo divers do this as do I.