Because of cold shock, falling into cold water without the protection of a wetsuit or drysuit is immediately life-threatening. But at what temperature does that happen?

 

Incapacitation - losing the use of your hands and then your arms and legs - can also happen very quickly. And unless you can get out of the water within roughly 30 minutes, hypothermia starts to become a survival threat.

 

We discuss these threats in detail in the sections below. We also explain why some people cool faster than others, and how a person can get used to cold water – a process called acclimation.  We also examine the difference between cold water lab research and the more intense experience of real victims who are fighting for their lives.