Hypothermia by:John Russell ~ Nov. 18 2005

What is cold water? Waters below 72 degrees are considered cold by divers. But Water temperatures below 91 degrees can cause Hypothermia. The 50's rules at a water temp of 50 degrees:

1 - An average adult person has a 50/50 chance of surviving a 50 yard swim in 50 degree water.

2 - A 50 year old person in 50 degree F water has a 50/50 chance of surviving for 50 minutes.

How can divers survive cold water?

1 - Don wetsuits (at least half a suit, pulled down to the waist) at the dock, in case of a boating accident, wetsuits provide floatation and warmth. Fishermen, buy and use a wetsuit in cold water.

2 - Heat is lost most in the head, neck and shoulders make sure the head is covered, a hood is desirable, but a hat will do. Keep your face out of the water. Heat loss also occurs in the armpits and groin, keeping those areas covered is also important

3 - Staying still in the HELP position (head high, knees to chest) or in the HUDDLE position (huddling with other survivors) and by wearing a PFD (life vest) can increase survival in 50 degree water from two hours (the survival rate for a person swimming or treading water without floatation) to seven hours -- add a wetsuit and hood survive up to thirty six hours (depending on the thickness of the suit).

WATER TEMP (Degrees in Fahrenheit)	EXHAUSTION	SURVIVAL TIME
32.5 or less	Under 15 min	Under 15 TO 45 min.
32.5 to 40	15 to 30 min	30 to 90 min.
40 to 50	30 to 60 min	1 to 3 hrs.
50 to 60	1 to 2 hrs.	1 to 6 hrs.
60 to 70	2 to 7 hrs	2 to 40 hrs.
70 to 80	3 to 12 hrs.	3 hrs. to indefinite
Over 80	Indefinite	Indefinite

For additional info check out: http://www.boatwashington.org/hypothermia.htm

Float Plan -- Download a float plan and fill it out before you next boating excursion at: http://www.marineweather.com/FR-FloatPlan.html

Dive Safe
Capt. John
Scubatampa.com ~ Sunsation Dive Charters