2nd stage and BOV on same bottle?

[LiteHedded]

I don't like the idea of my BOV being my sole access to the left bottle. It can be ruined with caustic and even the ISC BOV isnt as nice a breather as a real 2nd stage. The Shrimp definitely has more deadspace and doesnt breath quite as nice as a regular 2nd. The Shrimp also has a very finicky exhaust diaphram which can get goobers in it or just plain fail.

In "cave" configuration I have a stuffed short hose on the left side, long hose right.

In OW configuration where I have a deep BO on the left and 50% on the right, I still have the BOV off the left but the long hose is left sided too. So I can donate that deep BO to a stressed buddy.

what's the deal with the exhaust diaphragm?

 

[JonG1]

It's quite small and located in the purge button as opposed oto on a tee so it could in theory restirct exhale volume I guess in the event of a hypercapnic hit.

 

[JonG1]

Ask 2 cave instructors how to mark a jump and get 7 different answers.

I'm in the "I keep a short hose on a necklace bungee regardless of whether or not there's a BOV" when cave diving camp.

Is that to ensure you have a full spec reg available, to bypass an issue with the QD and in case of caustic?

Is it reasonable to expect to be able to flush/rinse caustic from a reg or could end up compromised in the event of ingress of caustic fluid/material?

 

[LiteHedded]

It's quite small and located in the purge button as opposed oto on a tee so it could in theory restirct exhale volume I guess in the event of a hypercapnic hit.

oh I see the BOV diaphragm not the loop exhast valve

 

[kensuf]

Is that to ensure you have a full spec reg available, to bypass an issue with the QD and in case of caustic?

Is it reasonable to expect to be able to flush/rinse caustic from a reg or could end up compromised in the event of ingress of caustic fluid/material?

1. Yes and no.

2. Maybe, but irrelevant because I have a reg on a necklace bungee.

 

[rjack321]

what's the deal with the exhaust diaphragm?

Its a dual inhale/exhaust diaphragm. The outer ring part act like an inhale diaphragm, the inner purge button part is the exhaust. If the exhaust is leaking (water) then the inhale parts dont work either. Basically it either works or is the worst possible wet breather ever.

 

[lostsheep]

Has anyone ever tried rinsing a BOV out after a caustic mid dive? Most likely you would not be going back on the loop but BOV in OC might be recoverable.

 

[rjack321]

Has anyone ever tried rinsing a BOV out after a caustic mid dive? Most likely you would not be going back on the loop but BOV in OC might be recoverable.

I'm sure its possible. But the tiniest drop of caustic getting into your lungs is potentially extremely serious so I just dont wanna rely on this.

 

[TuckerIdaho]

It's quite small and located in the purge button as opposed oto on a tee so it could in theory restirct exhale volume I guess in the event of a hypercapnic hit.

Have you tried doing a hard effort swim to see how it reacts to an extremely high rate of breath?

 

[rjack321]

Have you tried doing a hard effort swim to see how it reacts to an extremely high rate of breath?

I have but not at significant depth. "In theory" not diving a dense gas the BOV vs 2nd stage should be comparable to breathing air/EAN hard shallow. I didnt notice any diminished performance, although like most 2nd stages they all feel slightly different. I also wasnt breathing at CO2 hit levels either.