|Spoluautoři KIM Hong-Suk, CHOI Man-Joong, IM Chae-Wan|
In recent years, the iron making industry has become increasingly aware of an unwanted component in metal scrap-radioactive material. Worldwide, there have been over 40 cases where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases, contaminated metal consumer products were distributed internationally. To solve the problem, radiation monitoring of recycled metal scrap is being performed increasingly by mill operation companies and scrap processors. The monitoring does not, however, provide 100% protection. Improvement in radiation detection technology and government regulation can protect the steel industry from orphan radiation sources. However, the threat of radioactive materials in recycled metal scrap will continue for the future, and thus, poses regulatory policy challenges for both developed and developing nations. In this report, the incidents in which a final steel product and by-product contaminated by a radioisotope were distributed will be introduced. In addition, the optimization methodology of the operating the radiation portal monitoring system for cargo vehicles against unknown radioactive and nuclear materials will be advised.