钴-60操作热室窥视窗设计及性能分析

Shielding Design and Performance Analysis of Co Operating Hot-cell Peering Window

为避免放射性物质操作人员受到电离辐射的外照射,需要在放射性物质与操作人员之间设置带有窥视窗的屏蔽,而搭建窥视窗常用的材料为耐辐射玻璃和防辐射玻璃。为满足60Co密封放射源产品的操作要求,本文设计一套由国产耐辐射和防辐射玻璃构成的60Co操作热室窥视窗,并采用等比级数(G-P)逼近法和ANSI/ANS-6.4.3中的数据计算其照射量积累因子,根据此计算结果、玻璃的技术性能和基本物理公式分别分析该窥视窗的屏蔽性能和透光性。结果表明:该窥视窗的屏蔽性能达到了设计要求,可满足60Co密封放射源产品的操作要求。入射角的大小对窥视窗透射率的影响很大,当入射角超过60°后透光率迅速下降。

In order to prevent the external exposure caused by ionizing radiation, a biological shielding with a peer window should be set up between the operator and radioactive materials. The common materials used to construct a peer window are radiation-resistant or radiation-protective glasses. In this article, a set of 60Co operating hot-cell peering window, which is made of radiation-protective or radiation-resistant glasses produced in China, is designed to meet the operation requirement of 60Co sealed radiation sources. The gamma-ray exposure buildup factor of this peer window is calculated using Geometric Progression(G-P) fitting method and data from ANSI/ANS-6.4.3. Based on the calculation result, the performance parameters of different glasses and basic formulas, the shielding performance and light transmittance of this peering window are analyzed. The results show that the shielding performance of this peering window achieve the original design requirements and meet the operation requirements of 60Co sealed radiation sources;the incident angle of light has a great influence on the light transmittance which decreases rapidly when the incident angle of light is greater than 60°.