A device used to indicate water pressure in pounds per square inch is a blank gauge

• A. Barometer gauge
• B. Pressure gauge
• C. Differential gauge
• D. Vacuum gauge

Answer: (B)

The main idea is identifying an instrument that reads the pressure inside a water system. A pressure gauge is designed to indicate that pressure in pounds per square inch (psi), giving a direct readout of how strong the water pressure is in the piping or pump discharge. The other gauges serve different purposes: a barometer measures atmospheric pressure, not the pressure in a water line; a differential gauge shows the difference between two pressures rather than the absolute pressure at one point; a vacuum gauge reads low pressures (vacuum) rather than the typical system pressure. So, the device that directly indicates water pressure in psi is the pressure gauge.