The Swiss staging system is fairly commonly used for correlating core temperature and clinical signs: ▪︎ Stage I (35 – 32C; 90 – 95F): conscious, shivering ▪︎ Stage II (28 – 32C; 82 – 90F): altered mental status, not shivering ▪︎ Stage III (24 – 28C; 75 – 82F): unconscious, not shivering, vital signs present ▪︎ Stage IV (< 24C; < 75F): apparent death (but resuscitation possible!) ▪︎ Stage V (< 13.7C; < 58F): death due to irreversible hypothermia