Which term denotes pressure measured relative to atmospheric pressure?

Which term denotes pressure measured relative to atmospheric pressure?

• A. ASME B16.4
• B. Gauge Pressure
• C. ASTM A 234
• D. Light Hazard Occupancies

Answer: (B)

Gauge pressure refers to pressure measured with reference to atmospheric pressure. In sprinkler systems, gauges show how much pressure the water has above the surrounding air, so a reading of, say, 50 psi means 50 psi above atmospheric pressure. The absolute pressure would be the atmospheric pressure plus that reading, while differential pressure is the difference between two points. The other options are standards or classifications (not a type of pressure measurement), so they don’t describe how pressure is measured. Therefore, gauge pressure is the term that denotes pressure measured relative to atmospheric pressure.

Gauge pressure refers to pressure measured with reference to atmospheric pressure. In sprinkler systems, gauges show how much pressure the water has above the surrounding air, so a reading of, say, 50 psi means 50 psi above atmospheric pressure. The absolute pressure would be the atmospheric pressure plus that reading, while differential pressure is the difference between two points. The other options are standards or classifications (not a type of pressure measurement), so they don’t describe how pressure is measured. Therefore, gauge pressure is the term that denotes pressure measured relative to atmospheric pressure.