Abstract: To ensure long-term reliability of metrological performance of vehicle-mounted radiation monitoring system and to address the impracticality and high cost associated with frequent off-site calibration, This study proposes and validates a user-performed on-site calibration scheme. Using the widely adopted RS-700 vehicle-mounted radiation monitoring system as the test object, with standard radioactive sources and a high-pressure ionization chamber as references, the measurement repeatability, data consistancy, and statistical distribution of calibration factors across various distances are systematically evaluated. The results demonstrate the feasibility of user-performed on-site calibration. To ensure calibration accuracy, key operational parameters such as maintaining a distance between the calibration source and the detector greater than 0.5 meters and performing multiple independent measurements should be achieved with the aim to reduce random error.

Key words: vehicle-mounted radiation monitoring system, calibration, dose rate