calibration of gauges; calibration of electronic apparatus; calibration of pipettes; calibration of electronic equipment; calibration of machines; calibration of medical apparatus; calibration of detectors; calibration [measuring] services; calibration [measuring]; calibration of testing equipment; calibration of laboratory apparatus; calibration of construction testing equipment; calibration of sensors; calibration of measuring apparatus; calibration of analytical apparatus; calibration of laboratory equipment; calibration of instruments; calibration of measuring instruments; calibration services