The threshold dose for eye lens was significantly lowered, with a corresponding reduction in the lens equivalent dose limit from 150 mSv per year to 20 mSv per year on a 5-year average. Dose control for medical staff is a critical issue, and real-time measurements may be useful. Therefore, we examined the radio response characteristics of new real-time dosimeter RaySafe i3 with that of the older RaySafe i2, which are important for clinical use. They are real-time dosimeters. As a result, it was suggested that the response distance may decrease due to the placement of shielding such as a protection screen. In addition, it was confirmed that the system is not affected by in-hospital PHS and that stable measurements can be made pulse fluoroscopy. The i3 has comparable or better response characteristics compared to the i2 and pocket dosimeters, and is considered to be fully usable in clinical practice.

　The Regulations for the Prevention of Ionising Radiation Hazards have been revised in 2021. In line with this, lens equivalent dose management's importance is increasing in Japan. Therefore, we assessed and analyzed the lens dose of six percutaneous coronary intervention (PCI) surgeons in real-time using a new type of personal dosimeter. We found that the dose rates varied according to the different X-ray irradiation directions, the surgeon's face position, and the ceiling protective plate. In addition, the percentage of incorrect use of the ceiling protective plate could be calculated. This study showed the value of real-time analysis and the need to pay attention to the conscious use of the ceiling protective plate.