一、前言铁路运输放射性物质的种类和数量,随着原子能事业的迅速发展也随之增加,因此装卸工、货运员、车辆检修工人等受到小剂量长期作用的机会日益增多。国内外研究表明在小剂量长期作用下,照射所引起的反应或损伤有一定的累积作用。为了更好地贯彻执行国家《放射防护规定》确保铁路职 I. INTRODUCTION The types and quantities of radioactive substances in rail transport have also increased with the rapid development of atomic energy. Therefore, there is an increasing opportunity for operators, freight forwarders, vehicle maintenance workers and the like to be exposed to long-term effects of small doses. Domestic and foreign studies have shown that long-term effects of small doses, irradiation caused by the reaction or damage have a certain cumulative effect. In order to better implement the national “Radiation Protection Regulations” to ensure that the railway