Sooo.... what are the lessons? What should we as divers and dive instructors do to prevent this mishap from repeating itself?
Bear in mind that if this is not
the most common non-health-related scenario that ends in diver death, it's certainly one of the top three. "Diver ran out of gas, surfaced, had trouble, then sank and drowned" is repeated over and over and over and over in each year's mishaps. It is the "pilot continued VFR flight into IFR weather conditions, then crashed" of diving.
Lesson #1: If you don't know how much gas you have, you may run out.
- Recommendation 1.a: As a diver -
plan to leave the bottom with enough gas to get safely to the surface with some extra to handle problems. For that extra, the standard recreational "500psi" reserve is adequate in most cases; it certainly would have been in this mishap. This means you
actually have to do enough
gas planning to settle on a number. Whether you use a rule of thumb (500+100psi/10 FSW, for example), actually run the numbers based on your consumption rate, or something in between doesn't matter nearly as much as
doing it in the first place, making it a mandatory part of your pre-dive planning and saying it out loud to your buddy and getting an acknowledgment. "We'll start our ascent at no less than 700 psi" puts gas management on the brain before the dive begins and increases the probability that you'll actually do it under water.
- Recommendation 1.b: As a diver - monitor your gas supply throughout the dive with enough frequency to make sure you don't lose track of how much you've got. As a newbie this may mean clipping your gas gauge in front of you so that it's right there in your peripheral vision and you glance at it two or three times a minute; as you gain experience and confidence in your consumption rate you may be able to decrease the frequency considerably. However, regardless of how often you check the gauge,
gas supply awareness must be constant. If you are ever surprised at what your gas gauge says you need to change the way you monitor it so that your perception of how much gas you have at any given moment is accurate enough to assure a safe ascent at no less than the planned ascent pressure.
- Recommendation 1.c: Know how much gas your buddy has at all times. Whether you ask your buddy for a gas check or just check it yourself, you should know your buddy's gas status - again, how you accomplish this is not nearly as important as
doing it.
- Recommendation 1.d: As instructors - teach
gas planning and management. Under water, from pool 1 on, ask every student what their gas supply is at least every 15 minutes. Teach consumption rate (doesn't matter whether you teach SAC, SCR, RMV or XYZ, just teach consumption rate). Teach buddy gas supply awareness. Have your divers tell you not only their own gas supply but their buddy's as well during (15 minute) checks.
Lesson #2: If you can't get positively buoyant on the surface you may not be able to stay there.
Recommendation 2.a: As a diver - practice establishing positive buoyancy
every time you (intentionally) surface. Practice doing it by inflating your BC normally; by inflating your BC manually; by dropping your weights (or removing them before exiting - hand 'em up to the deck-hand, put them in the boat, put 'em back on, whatever - the idea is to practice getting rid of them). Make absolutely sure that the habit of establishing positive buoyancy is
automatic for you. As part of this practice make sure weights can be ditched at will and without difficulty even with a fully inflated BC.
Recommendation 2.b: As a dive buddy - Be able to jettison your buddy's weight. Be able to inflate your buddy's BC, normally and manually. Practice being a float for your buddy... sometimes the best thing you can do for a buddy in distress on the surface is to just get as buoyant as possible and let him/her climb up on top of you while they sort things out. After all, you've got plenty of gas for the job, right?
Recommendation 2.c: As an instructor - Teach "positive buoyancy on the surface" from pool 1. Teach buddy skills at establishing positive buoyancy. Any time a student surfaces and delays even a second establishing positive buoyancy, drill it into them. You cannot say "inflate your BC" too many times.
There are "tangential" lessons from a rescue perspective as well, especially considering cold water and dry suits and diving after a sinking diver, but the two essential lessons above are the ones that are common to far too many mishaps, and this one. They are the two that, if we take them to heart and drill them into every diver, we can have a real impact and drive down the number of fatal diving mishaps, and quickly.
Rick
