Dr. John Leach is an English researcher studying why some
people survive while others die in identical life-threatening
situations. He theorizes that any emergency situation can be
broken down into several phases -- pre-impact, impact, recoil,
rescue and post-trauma.
Before a disaster occurs, the most common psychological
response is “denial,” and the most common action is “inactivity.”
Most of us don’t believe a life-threatening diving emergency
will ever happen to us. Therefore, we tend to make no
preparations for emergency. How will you react when a disaster
does occur? Almost all of us would say something like, “I
will evaluate the situation, figure out the best course of action
from several choices, and follow it.” But in real-life emergencies,
very few people are actually capable of doing this.
During the impact phase of an emergency, when you either
live or die in the next few seconds or minutes, only 10 to 20
percent of people will remain relatively calm and be able to
“think, make decisions and act.” So up to 90 percent of us
will not be able to think, make decisions or act. Approximately
75 percent of people will “be stunned and bewildered,” writes
Leach. “They will not be able to think effectively and will act
in a semi-automatic, almost mechanical manner.” The remaining
10 to 15 percent will demonstrate “uncontrolled and inappropriate
behavior.”
A rare person will be able to function normally. A few more
will be able to think, make decisions and act, but they will not
be as sharp and clear-headed as normal. Most people won’t be
able to think their way through a problem but they will be able
to react without really thinking. The remaining small group
of people will panic or do things in other ways that actually
increase their chances of dying.
As mentioned, a few divers actually panic. A large number
of people demonstrate “paralyzing anxiety.” They can be literally
“frozen solid” with all of their muscles rigid, or more commonly commonly
they will be relaxed but incapable of movement because
their thought processes have become “circular” -- they think
the same things over and over and cannot move. Most people
experience perceptual narrowing or tunnel vision, incapable of
considering the entire situation but focusing only on one part
of it. They cannot think of several responses, they can only
think of one. The most common response, even during the diving
emergency, is denial: “This can’t be happening to me.”
Up to 90 percent of us won’t be able to
make decisions, think or act. |
Some people will demonstrate “hyperactivity,” appearing
to be purposeful and demonstrating leadership so many
bewildered survivors will follow them. Unfortunately, they
will often not be thinking clearly and the actions they get the
group to do are ineffective or inappropriate. They reduce the
chance of the group surviving. Many people will demonstrate
“stereotypical behavior,” partly denying the situation. They’ll
demonstrate will-learned behavior, even if it’s inappropriate
to the situation. Others will be irrational, which often reduces
chances of survival. Finally, many people will demonstrate
anger, some will feel guilt and a few will suffer psychological
breakdown during the survival phase. People give up and die
or they actively commit suicide.
Therefore, diver training is critical for survival. First, it
forces us to think and focus on the various emergency situations
we are likely to encounter while diving, and to figure out
what we will do. That reduces the chances of us denying the
danger and, more importantly, it allows us to do most of the
thinking ahead of time so that during the actual life-threatening
situation we can simply react. We don’t have to “solve the problem” because we already did that while training. The
second main benefit of training is to practice the response. We
can learn the response so that we can perform it without thinking.
Knowing that most of us won’t be able to problem-solve during the emergency reinforces the importance of practicing
emergency drills.
Before the dive, especially a high-risk one, I sit down and
think through all the likely emergencies, and plan how I’ll
respond to them. This determines what equipment I wear
during the dive, and reminds me to keep gear as simple as
possible. I plan what I’ll do if any piece of gear fails during
the dive. If you dive long enough, virtually every piece of gear
you wear will fail during a dive sometime.
At the beginning of the dive, preferably after I’ve entered
the water, I touch every piece of equipment I’m wearing and
think about what I’ll use it for. This ensures I can actually
reach it, and reinforces my memory of what gear I’m wearing
and where it’s located on my body. (I wear several completely
different gear configurations depending on the dive, ranging
from single-tank open circuit, to seven tanks and regulators, to
a closed circuit rebreather with up to four emergency bottles.
All these may be with or without a scooter, camera, survey
gear, line reels, etc.) As much as possible, you want to wear
one equipment configuration all the time to simplify your
response during an emergency.
Simply based on their psychological response to stress, 10
to 15 percent of the population should not start diving. Most
people can take up diving but many will be unable to think
at all during an emergency. However, they will be able to
react with a previously well-learned behavior. If it is appropriate
for the emergency, they’ll survive. If it’s not, they’ll die.
These people should restrict their diving to single-tank open
circuit, no decompression and shallow water less than 100
feet – “easy” diving. In this scenario, there is really only one
emergency response: exhale and make a controlled ascent to
the surface.
Some divers will be able to function minimally during an
emergency, so it’s reasonable for them to undertake slightly
more complex diving. This group includes advanced openwater
divers. Obviously, everyone who takes a basic scuba
course should not move on to advanced diving, but they
should periodically take refresher courses.
As the diving becomes more complex, more complex
responses are required during an emergency. Ideally, only the
10 to 20 percent of the population capable of active problemsolving
during an emergency should take up cave and technical
diving. One of the most dangerous situations I see is divers
moving into more advanced diving for all the wrong reasons;
they are trying to “keep up with their friends” or they are
trying to “prove themselves.” In cave and technical diving, I
often see divers who are trying to “prove they aren’t afraid”
when in reality they’re terrified. Limit your diving to what
is reasonable for you, take more training and practice your
emergency drills frequently to stay safe underwater.
David Sawatzky, M.D., is a diving medical specialist and has written
a diving medical column in the Canadian magazine Diver for the past
10 years. A version of this article appeared in a recent issue of Diver.