Reverse osmosis is a water purification process that uses a semi-permeable membrane to remove impurities, contaminants, and dissolved salts from water. In Salem, RO plants are widely used in homes, schools, hospitals, and industries to ensure access to safe drinking water. The popularity of RO systems in Salem is driven by the region’s hard water conditions and concerns about pollutants in groundwater. With an increasing awareness of health and hygiene, many residents prefer RO-treated water for drinking and cooking.