During hydrostatic testing, where should the pressure gauge be placed?

In hydrostatic testing for fire sprinkler systems, placing the pressure gauge at the top of the most remote standpipe is essential for accurately assessing the system's performance under pressure. This location ensures that the gauge measures the pressure experienced at the farthest point in the system, which is crucial for determining if all components are functioning correctly and maintaining their integrity under stress.

If the gauge were positioned at the main valve, bottom of the standpipe, or in the middle of the riser, it might yield misleading results. Those locations could indicate pressures that do not reflect the conditions experienced by the individual components at the most distant sections of the piping system. This could lead to an incomplete or incorrect assessment of the system's capabilities and safety, potentially resulting in critical issues going undetected.