Re: How long would an average adult male be able to survive in 55 degree water

Joe,

I couldn't find a specific formula that I could plug in the statistics you gave me, but you probably fall into the numbers below...
I got this information from a web stite (http://www.walrus.com/~belov/hypothermia.html)

Temperature Fahrenheit------Exhaustion/Unconscious----------Expected Survival
32.5-----------------------------------<15 min. -----------------------            10 to 45 min.
32.5 - 40----------------------------15 - 30 min. --------------------           39 to 90 min.
40 - 50------------------------------30 - 60 min. ---------------------          1 to 3 Hours
50 - 60-------------------------------1 - 2 Hours ---------------------            1 to 6 Hours
60 -70--------------------------------2 - 7 Hours ---------------------           2 to 40 Hours
70 -80--------------------------------3 -12 Hours -------------------            3 to Indefinitely
Over 80------------------------------Indefinitely ----------------------        Indefinitely

The web site also includes techniques that would improve your chances.  
Another web site (http://www.tntwebcraft.com/ccso/hypothermia.htm) gives 
very similar information, and includes pictures.


Here's a primary research article on the subject--thought it had some interesting info.

Medical Journal of Australia (1992) Nov 2;157(9):629-32 
Why some people do not drown. Hypothermia versus the diving response.
Author:  Gooden BA
Department of Physiology and Pharmacology, Queen's Medical Centre, University of Nottingham, UK. 

OBJECTIVE: To examine our present state of knowledge regarding the remarkable survival of some victims from prolonged submersion for an hour or 
more. Debate continues on the relative importance of the two explanatory theories--diving response and hypothermia. DATA SOURCES: A wide range of 
physiological, pathophysiological and clinical papers relating to the diving response, hypothermia and near-drowning, with emphasis on the period 1981-
1991. DATA SYNTHESIS: The normothermic human brain suffers irreversible damage if subjected to acute asphyxia for longer than 10 minutes. 
Significant resistance of brain tissue to hypoxia occurs only after its temperature has fallen from 37 degrees C to 30 degrees C or less. Body surface cooling 
depresses core temperature by only one-third of this drop in 10 minutes. Hence an additional factor, other than hypothermia, is required to explain 
survival from near-drowning. The idea that ingestion and aspiration of large amounts of cold water produce such a temperature drop lacks quantitative 
evidence. The diving response seen in marine mammals also occurs in humans but to a lesser extent; however, about 15% of volunteers tested exhibit a 
profound response. This response which starts immediately upon submersion prevents aspiration of water, redistributes oxygen stores to heart and brain, 
slows cardiac oxygen use and initiates a hypometabolic state. The possible influence of alcohol on these processes is considered.  CONCLUSIONS: Survival 
from prolonged near-drowning appears to depend upon a specific temporal interplay between the diving response and hypothermia, resulting in a 
protective state of hypometabolism.

Happy fishing,

Michael Crawford