How is that attached?

[Charlie99]

The idea is for the connection between the snap-bolt and the hose to strike a balance between easy to intentionally break and hard to accidentally break. It seems that current thinking says that O-rings are too easy to accidentally pop if you get hung up and that zip ties are too hard to cut if you're trying to disconnect. Cave line falls in the sweet spot - it's easy to cut with a knife or shears but very difficult to pull apart.

The original question was specifically about primary air sources.

I thought that regs were supposed to have a breakaway o-ring holding the boltsnap on so that, if the donating diver were on a deco reg, that in an extreme emergency another diver could just break away the clipped off primary reg. Are you saying that an OOA diver trying to grab a clipped off primary is supposed to be able to pull apart the cave line?

 

[Soggy]

I thought that regs were supposed to have a breakaway o-ring holding the boltsnap on so that, if the donating diver were on a deco reg, that in an extreme emergency another diver could just break away the clipped off primary reg. Are you saying that an OOA diver trying to grab a clipped off primary is supposed to be able to pull apart the cave line?

There is no need for a breakaway connection. Think it through and you'll realize that there is no scenario that would require this. The only reason why you'd have your long hose clipped off is if *you* are OOG or if you are on deco/stage gas. If you are on deco gas and you have a failure, you just switch to your backgas. If you are out of backgas, your buddy (also on deco gas) donates his deco gas (on a 40" hose) to you (remember, you always donate from the mouth). Your buddy then switches to his bungeed backup.

The original reason for the breakaway connection had to do with donating gas while on a rebreather and it doesn't apply to open circuit diving.

 

[Dive4Life]

The bolt snipe is usually tied off with #24 nylon rope. The knot used is a square not and mine is tied off a couple inches below the metal piece of the regulator. Hope this helps.

 

[SDAnderson]

The original question was specifically about primary air sources.

I thought that regs were supposed to have a breakaway o-ring holding the boltsnap on so that, if the donating diver were on a deco reg, that in an extreme emergency another diver could just break away the clipped off primary reg. Are you saying that an OOA diver trying to grab a clipped off primary is supposed to be able to pull apart the cave line?

Heh. Good question.

Clearly, the cave line isn't going to separate with anything less than a knife. Unless you haven't tied it correctly, in which case it may come undone at any moment and result in an involuntary donation of yet another snap-bolt to the gods of the deep. Been there, done that, too.

I won't pretend to be an authoritative answer on all questions DIR, but I've abandoned the o-rings (because they tended to break too easily) and gone to cave line. A couple of thoughts:

The axiom in DIR sometimes gets translated as "donate your primary" but I think the idea is to be prepared to donate the regulator you're breathing from - perhaps a subtle difference but an important one. If my primary is clipped off, it's because I'm breathing from a deco or stage bottle and I'm going to expect a panic-stricken diver to go for that regulator. The regulator I'm breathing also has the appropriate gas for the situation (the stowed regulator might not) and is the one I would donate in a non-panic situation, anyway.

Secondarily, if you're doing gas switches, you aren't a recreational diver and the standards for performance (including resistance to panic) escalate dramatically, IMNSHO. If my buddy is low on air, I expect both of us to know about it (and deal with it) long before he would be making a panic-stricken grab for my regulator. If he suddenly loses his air supply, I expect that my situational awareness and his calm and problem-solving capacity would allow us to deal with the problem before he starts to asphyxiate.​

As always, YRMV.