What is calibration?
Calibration is important wherever measurements are important, it allows users/businesses to have confidence in their instruments, results that they monitor, record and control. Calibration is the process of comparing a reading on one instrument, with another instrument that has been calibrated and referenced to a known set of parameters. The equipment used as a reference, should be directly traceable to equipment that is calibrated to the national standard, the UK’s national standard being UKAS.
Calibration of your measurement instrument(s) has two objectives. It checks the accuracy of the instrument and it determines the traceability of the measurement. In practice, calibration also includes repair of the device if it is out of calibration. A report is provided by the calibration expert, which shows the error in measurements with the measuring device before and after the calibration.
Why is calibration important?
An instrument measurement accuracy degrades over time, this is typically caused by wear and tear, however changes in accuracy can be caused by both electric and mechanical shocks and the environment the instrument is in. Why is calibration so important? The bottom line is, calibration of an instrument improves the accuracy of the measuring device so the instrument user can have confidence in their results.
when should you calibrate your measurement instrument?
Test equipment is usually calibrated annually, people/companies do this because it is easy to schedule. This may not necessarily be the best approach to take, most test instruments will drift over time, the newer the instrument the more frequently it needs to be calibrated, until its ability to reproduce measurements over a period of time has been established and is well understood.
A user might estimate a suitable recalibration frequency, based on previous experience of similar instruments used in similar environments, but it is only when the actual data from a series of successive calibrations of a particular instrument has been properly analysed that a meaningful recalibration frequency can be determined for that particular instrument.
What does traceability of calibration mean?
To provide confidence in the validity of the test equipment calibration results they must be traceable. This means the results on the instrument(s) calibration certificate need to be traceable to the standard used, and the results on the certificate for the standard are in turn traceable to the standard used for its calibration.
Do i need to get my test equipment calibrated?
Not necessarily, but if your test equipment isn’t measuring accurately then you won’t receive correct measurement readings.
Calibrations can be costly and that is one of the main factors when it comes to deciding not to calibrate your instrument(s). However, there can be even bigger costs when it comes to using an un-calibrated instrument such as product re-calls, how does the cost of a product recall stack up against the cost of calibrating an instrument(s).