This thesis examines the characteristics of exhaust gas cleaning systems (EGCS), more commonly known as scrubbers, and their environmental impact in the maritime sector, with a particular emphasis on the reduction of sulfur oxide (SOx) emissions. Although the maritime sector is crucial for global trade, it significantly contributes to air pollution, which has led to the implementation of stricter international regulations. Scrubber systems have been developed as a solution to reduce harmful gas emissions, enabling ships to use fuels with higher sulfur content while meeting environmental standards. The thesis presents different types of scrubber systems—open-loop, closed-loop, and hybrid systems—and analyzes their effectiveness in reducing emissions. It also describes the environmental consequences of using scrubbers, with a particular focus on the issue of washwater discharge into the sea, which poses a risk to the marine ecosystem. Additionally, it examines the regulatory framework of the usage of scrubber systems and their economic cost-effectiveness. A review of existing literature shows that scrubber systems can significantly reduce SOx emissions. However, their environmental impact requires further study and careful enforcement of regulations to minimize negative consequences for the environment. From an economic perspective, scrubbers offer shipowners the potential to reduce fuel costs, but their long-term sustainability depends on further development of scrubber technology and its continues adaptation to regulations and standards.