Radiation safety analysis of emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor / 中国辐射卫生

Objective Radiation safety of emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor is studied, the radiation protection method of emergency repair personnel in the reactor cabin is described, which provides a theoretical reference for personnel radiation protection and emergency repair time control. Methods The radiation was simulated by the Monte Carlo method for emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor, and the radiation was also analyzed with the radiation data measured by experiments in the reactor cabin under the natural circulation condition of the reactor. Results The neutron dose of external irradiation about reactor simulated computation was 140 μSv/h, and gamma radiation dose rate was 48 μSv/h. By experiment and calculation, the effective dose received by emergency repair personnel in the 30-minutein the reactor cabin was 2.2 mSv. Conclusions Under the natural circulation condition of the reactor, the gamma radiation is harmful to emergency repair personnel, but the focus of protection is different locations for maintenance. It's safe for emergency personnel to repair the reactor in 30 minutes in turn, wearing the respirators.

The Effective Reduction Method of Unstable Zygomatic Arch Fracture with Thermo-Splint

PURPOSE: The objective of this study is to propose an effective management of unstable zygomatic arch fracture. The reduction methods of arch fracture were relatively simple but the maintenance of reduction state is very troublesome. On this, authors introduce an effective management method of unstable zygomatic arch fracture. METHODS: Authors experienced 23 cases of unstable segmental zygomatic arch fractures and used Thermo- splint in all cases. All the arch fractures were reduced through Gillies' approach under the general anesthesia. After the reduction, the most effective suspension points were marked on the covering skin of the fractured arch. A needle of heavy nonabsorbable suture material was inserted toward the marking site under the reduced zygomatic arch. And then Therm-splint was dipped in the hot water, and we got the splint pattern of patient face. Reshaped Thermo-splint was trimmed and fixated with previous suspension suture materials. More additive suspension was done if necessary. The splint was applied for in two to three weeks postoperatively. RESULTS: In all the cases, good cosmetic and functional results were observed without severe complications. There were 4 cases of incomplete reductions but they also had no specific problems. There were no facial nerve symptom and scar(stitch mark). Postoperative slight tenderness and trismus were completely subsided after removal of the splint. CONCLUSION: The Thermo-splint safely protect and maintain the postoperative reduction state. The application, maintenance and removal were easy and simple. It could be reformed to any contour of face and had enough rigidity for supporting. Above all these things, effective prevention of displacement and easy manipulation were significant merit. Authors experienced good results with Thermo-splint, and would introduce it for another method of management of zygomatic arch fracture.