TEMPORAL DEPENDENCE OF THE RADIATION MONITORING INSTRUMENTS FOR AREA MONITORING USED AT RADIODIAGNOSTIC AND INTERVENTION FACILITIES

Area monitoring is a fundamental test at radiodiagnostic facilities to maintain an acceptable level of radiation exposure for employees and members of the public. Experimental measurements were taken in an ionising radiation calibration laboratory. Four area monitor instruments were used. Dose and dose rate measurements were measured in integrated and rate operating modes. The results show that precautions are necessary where the area monitor uses exposure times of <= 2 s. When taking measurements in rate mode for times <= 2 s, the area monitors evaluated show a tendency to underestimate dose rate, the inaccuracy was 41 %, and varied between 34 and 45 % for different energies. It is highly recommendable to work in integrated mode, inaccuracy varied from 2 to 35 %. For measurements taken with exposure times of >= 3 s, the average inaccuracy was 15% and the range was between 2 and 41 %.