Calibration · Glossary

What is a Reference Standard?

calibration hierarchyCalibration

A reference standard is the highest accuracy standard at a site, used to calibrate working standards rather than plant instruments.

Reference Standard Explained

The hierarchy runs from national standards to reference standards, working standards and finally field instruments. Each level should be several times more accurate than the one below.

Reference standards are handled carefully, used rarely and recalibrated by accredited labs.

Calculators for Reference Standard

CalculatorTest Uncertainty Ratio CalculatorFree online calculator with formula and worked example.CalculatorDeadweight Tester CalculatorFree online calculator with formula and worked example.

Free Downloads

Free downloadCalibration Master List Format in Excel with Due Date TrackerFree download in Excel and PDF.

Frequently Asked Questions

What is a Reference Standard?

A reference standard is the highest accuracy standard at a site, used to calibrate working standards rather than plant instruments.

What is a working standard?

A calibrator used day to day on plant instruments, checked against the reference standard.

Can one device be both?

In small sites yes, but it is then exposed to field wear.

Learn more on the blog

Calibration traceability: 6 proven links for trusted results

A practical guide on instrumentationblog.in with more detail on reference standard and how it is applied on real plants.

Read Full Article

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