A measurement method for surface absorbed dose rate of 90Sr/90Y skin applicators based on thermoluminescence detectors

90Sr/90Y applicators are currently widely used in the field of radiotherapy for superficial skin diseases. According to the relevant regulations of the GBZ 120-2020 health standard, the surface absorbed dose rate of the radioactive source needs to be corrected every two years, and the reference point dose rate needs to be detected once a year. In response to this, this work used thin LiF(Mg,Cu,P) and LiF(Mg,Ti) thermoluminescence detectors for measurement. The measurement results were compared with the reference dose rate data provided by the hospital. At the same time, an optimized ionization chamber was used for synchronous measurement to verify the accuracy of the measurement. This work independently designed a measurement device. The results show that the maximum error between the surface dose rate measured by the thermoluminescence detector and the data provided by the hospital is less than 10%. A calibration method for the surface dose rate of β applicators that can be traced and does not require the use of ionization chambers or films is proposed, providing a reference method for self-testing by institutions. Combined with practical applications, this method has a high degree of universality.