I have a rule on boats--everyone aboard, who is on deck, has to be visible to the skipper. This was especially true when we had a Symbol 42' sun deck , where when docking it seemed easier for some one to go down the ladder from the raised aft deck to step off onto the dock from the large swim step. The problem with that, is that I could not see that person, and if they slipped and fell in the water the 26" props and Cat 3208's would make mince meat of a person in very short order! We have seen several folks fall off the bow of boats and be run over.
A life jacket may keep your afloat--but getting back on the dock or boat may be much harder than you think. There are number of cases where a person was half in and half out of the water, and eventually succumbed to hypothermia--even in high 50's water.
Even more importantly is the cold water shock syndrome: There are actually as many deaths attributable to that in Kayakers as from drowning.
The cold water shock phenomena can cause death rapidly (within 2 to 5 minutes). At 60 degrees most people will experience some degrees of the cold water shock syndrome--which is a rapid heart beat, rise in BP, rapid respiration (up to 50 breaths a minute), severe vasoconstriction, decrease in breath holding ability and disorientation. In a percentage of people there will be immediate death. Others may have failure to swim or self rescue. There is also a "gasp" reflex, which causes inhalation--and if you are under water, it means water inhalation--perhaps drowning. This syndrome is completely out of your control, and may occur in some people in water temperatures as high as 77 degrees! The life jacket may hold you above water, and may allow the cold water shock syndrome to disappear--which usually takes 3 to 5 minutes.....
So self rescue is not as easy as you might think. I fell overboard at sea when I was about 10 (I had gone foreword to sweat up the halyards, and the deck was very slippery--no life lines or pulpits. My father was able to rescue me in several minutes, and he was strong enough to pull a scrawny kid out of the water. I also stepped from the boat to a dinghy right after WWII, when there were no docks and we were moored to pilings--but the dinghy was not there--and I remember pushing off the bottom--in about 10 feet of water. Again my dad rescued me. A few years later, I fell in off the dock--as I recollect I was helping someone push off their boat--much as described above. The last 60 plus years I have avoided falling overboard, but as I age, the risks become higher again...
