Hydrostatic Test Pressure & Working Pressure Rating for Fire System

HYDROSTATIC TEST PRESSURE & WORKING PRESSURE RATING FOR FIRE SYSTEM

July 28, 2025 Leave a comment

FIRE SYSTEM HYDROSTATIC TEST PRESSURE RATING:

The Hydrostatic test for a Fire water line System is to pressurize the System with water to a level beyond its normal operating pressure to identify any leakages and weakness in Pipes and its components to ensure that Fire System can withstand overpressure in Fire scenarios. * Hydro test can help to Identifying and repairing these leaks before the system is put into service to prevents potential safety hazards, environmental damage, and costly downtime. * This test is crucial for verifying that the Fire System can withstand potential pressures during a Fire event. * The Test Pressure is very important to identify the leakages, if pressure is too high than it may be damage Fire Pipes & it’s components and if the pressure is too low than it will not identify various leakages or weak point of the Fire System in potential overpressure scenarios.

Fire Sprinkler System Hydrostatic Test Pressure Rating

Code

Descriptions

NFPA 13, Section 29.2.1.1 Hydrostatic Tests Acceptance: New or modified sprinkler installations system working pressure Less than 150 PSI (10 Kg/Cm2) should a hydrostatic pressure test of no less than 200 PSI (13.8 Kg/Cm2) for 2 hours with zero loss in pressure at the reference gauge or visual observation of a leak. NFPA 13, Section 29.2.1.3 Where the system having working pressure above 150 PSI (10Kg/Cm2) then It must be tested to the system working pressure + 50 PSI (3.4 Kg/Cm2). Example: For 200 PSI Working Pressure have Testing Pressure of =14+3.4 =17.4 Kg/Cm2 NFPA 13, Section 29.2.1.4 Where fire pump is used for a system, testing pressure shall be determined by using the shut off pressure of the pump, excluding any limiting device. NFPA 13, Section 10.10.2.2 Underground Piping: All piping and attached appurtenances subjected to system working pressure shall be hydrostatically tested at 200 PSI (13.8 Kg/Cm2) or 50 PSI (3.5 Kg/Cm2) in excess of the system working pressure, whichever is greater, and shall maintain that pressure ±5 PSI (0.35 Kg/Cm2) for 2 hours. NFPA 13, Section 25.2.1.1 Systems Acceptance: All piping and attached appurtenances subjected to a working pressure less than 150 PSI (10Kg/Cm2) shall be hydrostatically tested at 200 PSI (13.8 Kg/Cm2) and shall maintain that pressure without loss for 2 hours. Portions of systems where working pressures in excess of 150 PSI (10.4 Kg/Cm2) shall be tested at a pressure of 50 PSI (3.5 bar) in excess of working pressure NFPA 20, Section 14.1.2.1 Suction and discharge piping shall be hydrostatically tested at not less than 200 PSI (13.8 Kg/Cm2) pressure or at 50 PSI (3.4 Kg/Cm2) in excess of the maximum pressure to be maintained in the system, whichever is greater. The pressure shall be maintained without loss for 2 hours NFPA 25, Section 6.3.2.1 A working pressure less than 150 PSI (10Kg/Cm2) shall be Hydrostatic tests of not less than 200 PSI (13.8 Kg/Cm2) pressure for 2 hours, or at 50 PSI (3.4 Kg/Cm2) in excess of the maximum pressure, where maximum pressure is in excess of 150 PSI (10.3 bar), shall be conducted every 5 years on manual standpipe systems and semiautomatic dry standpipe systems, including piping in the fire department connection. NFPA 25, Section 13.7.4 The piping from the fire department connection to the fire department check valve shall be hydrostatically tested at 150 PSI (10 Kg/Cm2) for 2 hours at least once every 5 years NFPA 14 , Section 11.4.1 requires all FDCs to be tested hydrostatically at not less than 200PSI (14 Kg/Cm2) or 50PSI (3.5 Kg/Cm2) in excess of the system working pressure, whichever is greater for a duration of 2 hours. IS 15105:2, Section 10.1.6 The installation piping (from the pumphouse up to the installation valve and also the installation piping with sprinklers) shall be capable of withstanding for two hours a pressure equivalent to 150% of the maximum working pressure. (maximum Pressure may be derive from Fire Pump Data Sheet) IS 13039, Section 7.1 After installation the system should be capable of withstanding pressure equal to 150% of the maximum working pressure for 2 hour. (maximum Pressure may be derive from Fire Pump Data Sheet) IS 3844 , Section 8.1 The system should be tested before use by charging with water to a pressure of 700 kPa (7 kg/Cm2) measured at the inlet for a period of at least 30 minutes. During this period, an inspection of the system should be done to check that no leakage of water is taking place at any of the joints or landing valves and the pressure in the system does not drop by more than 50 kPa (0.5 Kg/Cm2). BS 9251, Section 6.2.2 The installation pipework should be pressurized to a minimum pressure of 15 bar (15.2 Kg/Cm2) or to 1.5 times the maximum working pressure, whichever is the greater, for 1 hour. If the sprin…