If a pressure gauge reads 50 psi, what is the accuracy of measurement based on ±1% of reading?

• A. ±0.25 psi
• B. ±0.5 psi
• C. ±1 psi
• D. ±0.75 psi

Answer: (B)

To determine the accuracy of the pressure gauge reading based on ±1% of the reading, we first need to calculate 1% of the measured value, which is 50 psi.

1% of 50 psi is calculated as follows:

1% of 50 psi = 0.01 × 50 psi = 0.5 psi.

Since the accuracy is expressed as ±1% of the reading, it means that the measurement can vary by 0.5 psi above or below the actual reading. This indicates that the precision of the gauge is reliable within that range, which is ±0.5 psi in this case.

This understanding of accuracy is crucial in instrumentation and process control, as it helps operators and engineers understand the potential error margins in their measurements, which can be critical for process safety and efficiency.