How cold is death?

[scubacope]

Not talking about an ice dive but at what point does water temperature become deadly? Obviously everybody is different but with a 6mil suit when do you say - no way? Also there are regulator issues involved right? Leave out dry suit and tech dive out of this. Pretend you are on your favorite spot and as you descend the water gets really cold. I believe your body would be saying you are too cold get out. Shivering would be one sign what are the others?

 

[fisherdvm]

Expected Survival Time in Cold Water
Water Temperature
(first time noted) Exhaustion or Unconsciousness in
(second time noted) Expected Survival Time

70–80° F (21–27° C)
3–12 hours
3 hours – indefinitely

60–70° F (16–21° C)
2–7 hours
2–40 hours

50–60° F (10–16° C)
1–2 hours
1–6 hours

40–50° F (4–10° C)
30–60 minutes
1–3 hours

32.5–40° F (0–4° C)
15–30 minutes
30–90 minutes

<32° F (<0° C)
Under 15 minutes
Under 15&#8211;45 minutes

 

[fisherdvm]

However, a few individual can mentally increase their core body temperature to above normal, and are able to withstand cold temperature for extended time. I think a woman swam 1 mile in 32 F water, and 32 F air temperature in the anartic. She was able to bring her core temperature to above 102 degree before the swim.

 

[parrothead600]

I haven't found any water that is too cold for a 6.5mm wetsuit.(Fresh water can't get any colder than 32 )With part of my face exposed, I have no problem feeling the change in temp @ the thermocline. If I start to get chilled, the first thing that I notice is that I get a shiver when I inhale.

BTW, Welcome to :sblogo:

 

[fisherdvm]

I haven't found any water that is too cold for a 6.5mm wetsuit.(Fresh water can't get any colder than 32 )With part of my face exposed, I have no problem feeling the change in temp @ the thermocline. If I start to get chilled, the first thing that I notice is that I get a shiver when I inhale.

BTW, Welcome to :sblogo:

I'll bet you'll get cold if that water is 100 ft and your suit is compressed to half its thickness

 

[The Kraken]

Any temperature of water which removes caloric heat from the body faster than be body can generate the amount of heat required to support human life as we know it.

It's all just a matter of time . . .

the K

 

[TSandM]

As the Kraken says, it's only a matter of time . . . It's a balance between the heat you can generate and the heat lost to the environment, and this is true whether you are in water or air. You increase the heat generated by increasing your activity level and having more metabolic mass (ie. muscle). You decrease the heat lost to the environment by increasing insulation, whether that's by having a layer of poorly perfused tissue under the skin (fat) or by wearing various kinds of exposure protection. It is probably possible to be sufficiently insulated to spend as much time as you want in water as cold as you can swim in, but you wouldn't be very mobile or very comfortable doing it.

Hypothermia is a very sneaky thing. Shivering is the obvious sign and usually commands your attention, but when the core temperature falls far enough, shivering stops. Even at the shivering point, your dexterity is diminished and your ability to think well and make good decisions is impaired. Pushing the comfortable time in the water, at any water temperature, is decidedly unwise.

 

[Pearldiver07]

You decrease the heat lost to the environment by increasing insulation, whether that's by having a layer of poorly perfused tissue under the skin (fat) or by wearing various kinds of exposure protection.

Always a proponent of "Bio-prene" !!

 

[irishsquid]

I haven't found any water that is too cold for a 6.5mm wetsuit.(Fresh water can't get any colder than 32 )With part of my face exposed, I have no problem feeling the change in temp @ the thermocline.....
BTW, Welcome to :sblogo:

Dived last Sunday in the local quarry. Water was 44F and I made it for 46 mins. in a 5/4/3mm. The best I could tell, using part of my face exposed; the thermocline was from the surface to the bottom. Brrrrrrrrrr!!!!!!!!!

 

[scubacope]

You start watching "Titanic" and "Deadliest Catch" and these questions come up in conversation especially when you are a landlocked diver. I have never called a dive early because of temperature yet. However I have ascended a few feet to get out of the thermal.

Parrothead600- Thanks. Glad to be here. Should be hearing alot from me this summer. My 18 year old son and best friend got certified this past summer. 2008 should be a year under water!