Kim, Y.-S.; Ryu, J.-H., and Lee, H.-T, 2021. A study on buoyancy maintenance time and underwater weight according to changes in lying-down posture during coastal safety education. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 619–622. Coconut Creek (Florida), ISSN 0749-0208.

In this research, an experiment was performed to calculate body weight data and mass data for the subject's supine position using a three-dimensional image analysis program and an underwater weighing machine. This is to raise people's awareness of maritime safety and to revise the guidelines for maritime safety education by preparing institutional policies. First, the buoyancy retention time according to the change in lying down posture was the longest in P1(head-up), and in the order of P2(horizontal) and P3(attention) with statistically significant difference. Second, the change in body weight (buoyancy) according to the change of the lying down position was found to be the heaviest in P3, followed by P2 and P1 with significant difference. Summarizing the results of this study, the best way to maintain the buoyancy according to the change in lying down position during survival swimming is P1 that allows the body to float on the surface for the longest time. It also showed the heaviest underwater weight at P3, so it was found that incorrect upper body stance during survival swimming could affect buoyancy, survival rate. Lastly, even a person who is proficient in swimming has a very limited survival time at low temperatures, so it is considered that the above-mentioned efficient floating method and continuous swimming and application in education are necessary.