The document discusses emissions to air from ships and strategies for reducing air pollution beyond regulatory compliance. It outlines various air pollutants emitted from ships, such as nitrogen oxides (NOx) and sulfur oxides (SOx), and regulations from the International Maritime Organization (IMO) to limit these emissions. Methods for reducing ship emissions are discussed, including using low-sulfur fuel, exhaust gas cleaning systems, and operational measures like slow steaming. The document emphasizes that reducing emissions requires approaches throughout the combustion process, from fuel preparation to exhaust cleaning.