This study was to analyze the effects of sudden rise on cortisol and human symptoms in the situation of rescue at river. The experimental results are as follows. The subjects were A, B and C and the values of cortisol elevation before and after diving were 6.30 ug/dl, 6.50ug/dland 6.57 ug/dl respectively. However, in the subject D, the elevation value of cortisol before and after diving was significantly elevated by 11.00 ug/dl. The reasons for this are thought to be the increased anxiety due to the inferiority of the underwater view and the depletion of physical strength through the tension during the sudden rise. The subject E showed significantly lower cortisol elevation before and after diving, as 4.28 ug/dl, because the age of E was the youngest of the subjects and the anxiety was low due to abundant experience of deep sea diving.

Fatigue is 7 to 8 and anxiety is 7 to 9. Both showed high values. Psychological strain increased fatigue in underwater search and poor visual field seemed to increase anxiety. The common symptoms of the subjects were dizziness. This is considered to be due to the fact that a small amount of nitrogen bubbles is generated due to the sudden pressure difference during the sudden rise, which causes the human body to be stressed, thereby influencing the increase of the cortisol concentration. If you have not only dizziness but also vomiting, you may be suffering from decompression sickness symptoms. The results of the study will be provided as empirical data on safe underwater search activities of rescuers.