preventing and handling emergencies 285
water. Wet conditions such as rain, sleet, snow, or waves that splash aboard accelerate
hypothermia in air. But what happens when you fall into the water unprotected?
In water, your body loses heat twenty-fi ve times faster than in air. You’ll eventually
become hypothermic in water temperatures under about 95°F (35°C)!
You must take every precaution to prevent overboard emergencies. Be on the
lookout for the visual warning signs of hypothermia in the accompanying chart.
Later in this chapter, we will discuss survival tactics and treatment of individuals
in various hypothermic stages.
COLD-WATER IMMERSION: WATER TEMPERATURE 77°F
(25°C) AND BELOW
Boating in cold water calls for special precautions. Th e accompanying statistics
from the National Oceanographic Data Center show average winter seawater
2050607090100(^0) Montauk, NYAtlantic City, NJLewes, DECape Charles, VABaltimore, MDAnnapolis, MDCape Hatteras, NCCharleston, SCSavannah Beach, GADaytona, FLMiami Beach, FLKey West, FL
10
30
40
80
Seawater Temp.
21
16
27
38
10
4
–18
–1
–7
°F °C
–12
32
Th ese statistics from the National Oceanographic Data Center show average summer
seawater temperatures along the central and southern Atlantic coasts.
Severity Body Core Visual Signs
Mild 98.6F (37C)–96F (36C) Shivering; difficulty moving or completing simple tasks
95F (35C)–1F (33C) Shivering uncontrollably; slurred speech; amnesia
Medium90F (32C)–86F (30C) Shivering stops completely; unable to move; muscles not responsive
85F (29C)–81F (27C) Irrational behavior; respiratory system slows dramatically
Severe 80F (27C)–78F (26C) No reflexes; unable to communicate; heart arrythmia
78F (26C) or less Death
Th e visual warning signs of hypothermia.