Technological advances in blue laser sources are expanding the possibilities for using high-power laser radiation, particularly in the range of 1 kW and above, in marine environments, due to the reduced absorption of laser radiation below 550 nm in water. These developments are creating new opportunities for high power laser underwater applications. One key application is the removal of biofouling from submerged technical surfaces like ship hulls by causing lethal damage to attached organisms. This research investigated the effect of radiation power density on lethal damage to organisms, focusing on naturally grown biofouling. Experiments were carried out with different power densities in the range from high-power blue light emitting diodes (LED) at 0.02 W/mm² to high-power blue lasers at 3.88 W/mm². These results help to understand the relationship between radiation parameters and biological responses, which is crucial for optimizing environmentally friendly technologies.