1. Connect gauge to a calibrated pressure source. 2. Check zero at atmospheric pressure. 3. Apply pressure in steps (0%, 25%, 50%, 75%, 100%). Record readings. 4. Reduce pressure in steps back to zero. Record again. 5. Compare gauge vs. standard; note errors. 6. Adjust zero/span if out of tolerance. 7. Repeat test until within limits. 8. Document results and label the gauge. #pressuregauge #instrumentation #InstrumentationEngineering | Instrumentation World