Aoraki Dragon Boat
Association (Inc)
Christchurch, NZ

Water Safety - practical steps for Dragon Boating

Aoraki's Safety Manual has DB-specific procedures for making you safe. But there are general water safety rules that we should all be aware of.

Hypothermia - the risks in cold water:

"It is impossible to die from hypothermia in cold water unless you are wearing flotation, because without flotation – you won’t live long enough to become hypothermic"

What happens to people who get in really cold water?

Below, say, 10 degrees C, significant physiological reactions occur:

1. You Can’t Breath: cold water immersion produces a cold shock response, characterised by increased heart rate and blood pressure, uncontrolled gasping, and sometimes uncontrolled movement. Lasting anywhere from 30 seconds to a couple of minutes depending on a number of factors, the cold shock response can be deadly all by itself. In fact, of all the people who die in cold water, it is estimated that 20% die in the first two minutes. They drown, they panic, they take on water in that first uncontrolled gasp. For those with heart problems, the cold shock may trigger a heart attack. Surviving this stage is about getting your breathing under control, realizing that the stage will pass, and staying calm.
2. You Can’t Swim: when the water is cold – none of us can swim for very long. The second stage of cold water immersion is called cold incapacitation. Without insulation your body will make its own. Long before your core temperature drops a degree, the veins in your extremities will constrict,  you will lose your ability control your hands, and the muscles in your arms and legs will just stop working well enough to keep you above water. Without some form of flotation, and in not more than 30 minutes, the best swimmer among us will drown – definitely – no way around it. Without ever experiencing a drop in core temperature (at all) over 50% of the people who die in cold water, die from drowning perpetuated by cold incapacitation.
3. You Last Longer than You Think: In water of say 5 degrees C, it typically takes a full hour to approach unconsciousness from hypothermia, the third stage of cold water immersion.  But remember, you must be wearing flotation to get this far. We are all different in this regard, but it probably would have taken another hour to lose consciousness, and an hour after that to cool your core to the point of no return. The bodies efforts to keep the core warm – vasoconstriction and shivering – are surprisingly effective. Shivering and blood shunting to the core is so effective, that twenty minutes after immersion, you can have a fever of 37.9.
4. Out of the Water is Not Out of Trouble: The final killer of cold water immersion is post-rescue collapse.  Hypothermia does things besides making everything colder.  Victims are physiologically different for awhile.  One of the things that changes is called heart-rate variability.  The hearts ability to speed up and slow down has been effected.  Getting up and moving around requires your heart to pump more blood, being upright and out of the water is also taxing, then any number of other factors collide and the heart starts to flutter instead of pump – and down you go.  Victims of immersion hypothermia are two things; lucky to be alive, and fragile.  Until everything is warmed back up – out of the water and dry is good enough – mobility comes later.

See also tips on recognising if a person is drowning.