According to the "Building Water Supply and Drainage Design Standards" (GB 50015-2019) Article 4.4.12, the following structures and equipment drains and domestic drainage piping system should be taken indirectly: ① domestic drinking water storage tanks (pools) of the drain and overflow pipe; ② water boiler, water heater drainage; ③ Medical sterilization and disinfection equipment drainage; ④ evaporative cooler, air conditioning equipment condensate drainage; ⑤ storage of food or beverages in the refrigerated warehouse floor drainage and chiller frost water tray drainage.