The Industrial Test Calibration article provides you information about testing equipment, measuring equipment and inspection equipment calibration requirements.
Measuring, inspection and testing equipment calibration is mandated by most construction and in-service codes.
The manufacturer quality control system is needed to define a process for the calibration of measuring and testing equipment to ensure the reading values are correct and accurate.
The calibration must be done in independent laboratory, which is accredited for calibration tests. There is different between calibration and adjustment.
The calibration is done in a reference laboratory, but adjustment is the accurate setting of measuring tool before application.
For example, when you are setting your ultrasonic thickness reading equipment with metallic test block, you are doing adjustment.
But when you are sending your test block to the reference laboratory, you are doing calibration.
The calibration process must be well-defined in a quality control program, and it is necessary that a list of measuring and inspection equipment be available with their calibration status, such as the date of last calibration, expiry date, and acceptable tolerance ranges, etc.
The calibration certificates also need to be available. These are general measuring and inspection tools, which need to be calibrated periodically: