Calibration in the oil and gas industry refers to the process of adjusting and verifying the accuracy of measuring devices and instruments used in the exploration, production and transportation of oil and gas. This includes devices such as flowmeters, pressure gauges and temperature sensors. Calibration helps to ensure that these devices are providing accurate measurements, which is crucial for safe and efficient operation of equipment and processes. It also helps to detect and prevent equipment failures and to optimize performance of the equipment.