Stearns Safety & Survival 24MSPT-1 - Manual (Page 12)

12
VIII. HYPOTHERMIA
Prolonged exposure to cold water causes a condition known as
hypothermia - a substantial loss of body heat, which leads to exhaustion
and unconsciousness. Most drowning victims first suffer from hypothermia.
The following chart shows the effects of hypothermia:
PFDs can increase survival time because they allow you to float without
using energy treading water and because of their insulating properties.
Naturally, the warmer the water, the less insulation you will require. When
operating in cold waters [below 60º F(15.6º C)] you should consider
using a coat or jacket style PFD or a Type V Thermal Protective PFD as
they cover more of the body than the vest or belt style PFDs.
HOW HYPOTHERMIA AFFECTS MOST ADULTS
Water Temperature Exhaustion or Expected Time
º C º (F) Unconsciousness of Survival
0.3 (32.5) UNDER 15 MIN UNDER 15 TO 45 MIN
0.3 TO 4 (32.5 to 40) 15 TO 30 MIN 30 TO 90 MIN
4 TO 10 (40 to 50) 30 TO 60 MIN 1 TO 3 HOURS
10 TO 16 (50 to 60) 1 TO 2 HOURS 1 TO 6 HOURS
16 TO 21 (60 to 70) 2 TO 7 HOURS 2 TO 40 HOURS
21 TO 27 (70 to 80) 2 TO 12 HOURS 3 HOURS TO INDEFINITE
Over 27 (Over 80) INDEFINITE INDEFINITE