MikeB wrote:Yes - I understand that would be the plan. But sharing gas off a short primary hose, even in a recreational setting is far from ideal. The divers are forced to be pretty much on top of each other, which can result in even higher stress levels (adding to those of the current OOG situation). In this case, the diver would need to donate from the mouth to the OOG diver. I think this is great, but is would be better to do it with a hose of a suitable length.
Simple fix to that is to use a 7ft hose on your primary. I should have mentioned that. Its one of those instances where more is less! More hose but routed nicely so less mess!
The donating diver then has to switch onto the combined inflator/octi. I don't really have any personal experience with these, apart from seeing a few incidents caused by them (Greg do you remember that incident with a RB diver at the cowshed a while back? Think Phil was diving with him at the time...). I don't really understand why you would remove a potential third regulator from your arsenal.
I dont recall any incident where the octi inflater was to blame ( maybe I miss understand your statement).
How many regulators do you need? There comes a point where they just get in the way and cause more issues than what they can solve.
eg. I dont have OC access to my on board O2. I could add a 2nd stage but where would it go? I could bungy it around my neck. But the hose routing to it would be a right pain. It would also get in the way when I remove the loop from my mouth. At best it may give me access to 600l of O2 but more than likely it will only be 300l. At worst the regulator could free flow and I could lose all that O2.
Having a second gas source can sometimes add a sense of security that isn't warranted. Most of these devises when used by recreational divers are positioned in a way that they are not easily accessible, and they are often poorly maintained.
Dont forget not filled properly.
Do there spare airs have gauges? I think some have button gauges but they are far from accurate. Can you turn them off or do they stay on all the time ( and slowly leak out). Unless you are filling it before every dive then how do you know whats in it?