So "military" standards are inappropriate; and you say "science diving" standards are also. I have some trouble when we define things by what they are not rather than what they are. Granted, the requirement for rescue diver types is likely predicated on being under a chopper, but the requirements for a science diver, in terms of diving itself are those imposed by the same environment that recreational divers are subject to.
It is the consensus opinion, of those professionals, whose full time concern (and only concern, with no other axes to grind) is minimizing the risk that the divers they supervise are exposed to that wearing a snorkel involves far less risk than not doing so.
The only conditions that science divers are REQUIRED to NOT have a snorkel are saturation and overhead environments like under the Antarctic icepack. Each of us has every right to go to hell in the hand-basket of our choice, but your participation is the discussion here places some obligation to participate in the dialectic at a level that is more insightful than unsupported blanket statements like, "I am no more efficient on the surface with a snorkel than I am without one."
What I said was that most of the folks that I have had a chance to interact with who disdain the use of a snorkel do not know how to properly wear one and also lack some of the skills critical to using one. I stand by that.
I believe Wayne just said, "When I dive in the open ocean," which is not Cozumel.
No, you are missing the major point, which is there is almost always a trade off when you decide to carry a certain piece of gear, carrying it exacts an immediate cost or increases a risk in some fashion and that must be weighed against the lowered risk or other advantages that carrying it provides. There is also a longer term cost that relates to both initially learning to use the item in fashion that minimizes costs and maximizes benefits as well as the costs associated with routine practice and drill that assures that the costs are kept minimized and the benefits stay maximized. The initial and longer terms costs of a snorkel are so infinitesimally small that even if the advantage is, as you describe it, "under very limited circumstances," I submit that it comes out on the positive side of the balance sheet.
Similarly I carry an emergency pouch on every dive. It contains flares, smoke, signal mirror, safety sausage, small light, etc.
There are costs, in terms of cash, maintenance and drag, to carrying this. But those costs are tiny when compared to the reduction of risk that this pouch might provide. Now ... I've never needed it to date. If I needed it tomorrow that'd be less than 1 in 10
4, so should I stop carrying it because the odds are so low?
When it comes to a snorkel, let's just take a few possibilities, ones that relate to rescue, and not by any means a census of all that might occur:
- We agree that if you are under a helicopter a snorkel makes life much, much easier. It is the difference between being able to be an active participant in what is going on and a passive victim.
- If you have trained in mouth-to-snorkel rescue breathing you are able to transport a victim at virtually the same speed that you can swim, over a rather long distance, whilst providing in excess of 20 breaths per minute. I have not found any other technique that makes this possible.
- It also serves in place of a pocket mask or other form of shield which you are unlikely to have with you out in the ocean.
- If you are providing a tired diver assist, either with the victims hands on your shoulder or with a fin push you will be, more or less, face down in the water, especially if you are wearing a BP/W. A snorkel makes both these assists much, much easier.
Any one of those four items, each of which is far more likely than needing a parachute flare or smoke, greatly overpowers the minuscule cost(s) of taking a snorkel out on a dive.
