A medium-sized biopharmaceutical manufacturer in Jiangsu runs a full-process purified water system, including multi-media filtration, activated carbon filter, two-stage RO reverse osmosis, mixed ion exchange bed and finished water storage tank. Purified water is used for reagent preparation, equipment cleaning and injection auxiliary production, requiring stable conductivity ≤ 2.0 μS/cm (25°C) to meet GMP standards.