Acid washing is a cleaning process used primarily on surfaces like concrete and swimming pools. It involves applying a diluted acid solution, typically muriatic acid, to remove stains, dirt, and mineral deposits. This method helps restore the original appearance of the surface and can also prepare it for further treatments, such as sealing or painting. The acid reacts with the contaminants, breaking them down and allowing them to be easily rinsed away. While effective, acid washing requires safety precautions, including protective gear, due to the corrosive nature of the chemicals involved. Proper ventilation and disposal of waste are also essential.