Call an expert
+44 141 880 7455
Use a form
Chat to an expert

What is the difference between calibration and verification?

Calibration and verification are two distinct processes that are often used in different contexts, especially in scientific, engineering, and measurement-related fields. Here's a brief explanation of each term:


Definition: Calibration is the process of comparing the measurements or readings of an instrument or device to a known standard or reference to ensure accuracy.

Purpose: The main goal of calibration is to determine and correct any deviations or errors in the measurements made by an instrument. This helps ensure that the instrument provides accurate and reliable results.

Process: During calibration, the instrument is adjusted or fine-tuned so that its readings align with the established reference standards. This is often done by a service engineer or technician using specialized equipment.


Definition: Verification, on the other hand, is the process of confirming that an instrument or system meets specified requirements or specifications without necessarily adjusting or modifying it.

Purpose: The primary purpose of verification is to check whether a system or instrument is operating within acceptable limits and is capable of producing reliable results. It is more about confirming performance rather than adjusting for accuracy. For certain instrumentation devices, there will be a legal or quality management requirement for verification and can only be used if they have been verified by national standards. Therefore, instrumentation will have to be verified on a periodic basis to prove it operates within the maximum permissible error required.

Process: Verification involves testing or checking the instrument against predetermined criteria or specifications. This can include functional tests, performance checks, and comparisons to established standards to ensure that the instrument is functioning correctly.

JWF offer bespoke calibration and verification services for a wide range of instrumentation to ensure quality and accuracy of measurement.

Calibration Services

Our service engineers are fully trained to offer on-site and in-house calibration services for your measuring instruments covering all industry sectors.

Calibration Laboratory

Our calibration facility offers in-house calibration covering a wide range of instrumentation including flow, pressure, temperature and level. Our calibration equipment is certified and traceable to national standards.

On-site Calibration

Our service engineers are fully trained to offer on-site calibration using our portable rigs. This is convenient for customers as it removes the need to send instruments away for calibration having little impact on process.

Verification Services

On-site verification is performed by our highly trained service engineers. They provide instrumentation verification in-situ therefore no need for process shutdowns.

ABB Ability verification

Our service engineers use ABB Ability™ software for verification on the range of ABB instrumentation while in-situ. The software automatically generates a verification report providing a PASSS/FAIL and detail any problems.

FLEXIM ultrasonic non-invasive verification

Our service engineers use a portable FLEXIM clamp-on ultrasonic flow meter to verify against your inline flow measurement device. A verification report shows the measured error between both the measurements.

Site Standard

JWF have agreed on-site standards with a number of customers which includes verification and calibration. For example, 3 years of meter verification followed by calibration at year 4. This allows sites to place maintenance and reduce overall costs and shutdowns.

Back to Insights