Highly efficient manufacturing processes in which innovative technologies are continuously integrated are essential for a globally competitive European maritime industry. Promising optimization potential lies in the welding of thick sheet metal. The use of new high-power diode lasers with output powers of up to 60 kilowatts can replace conventional welding processes and significantly improve welding quality and efficiency. In addition to the welding process development with extremely high laser powers, ensuring laser safety is a major challenge for adequate employees’ protection. This work aims to investigate the spatial distribution of laser radiation backscattered from the laser process zone into the hemisphere above the sheet metal. The results of the scattered radiation measurements performed are used to estimate the amount of thermal energy introduced from the laser process zone into a possible protective shielding against the scattered radiation. The de rived maximum temperatures finally allow a suitable dimensioning of the shielding.