这三周中，他每次在近1.7°C（28.94°F）温度的水中游大概20分钟，再少0.3°C就是海水的冰点。
During each of the swims that were spread over three weeks , Pugh spent about 20 minutes in water temperatures as low as minus 1.7 ° C ( 28.94 ° F ) , just 0.3 ° C shy of the freezing point of salt water .
海水冰点