An imaging plate (IP) system was used as an effective detector for direct measurement of radioactive surface contamination. The IP system displayed images designating the locations and extent of fixed surface contamination of uranyl acetate. The amount of radioactive waste produced during decontamination was reduced because the contaminated spots could be isolated; furthermore, creation of radioactive dust during removal of contamination was prevented because the contaminated spots could be removed without being pulverized. The images were used in efficiently and safely isolating the location of fixed surface contamination. The IP system surface contamination detection limit for uranyl acetate was 2.5 × 10−3 Bq cm−2, a value much lower than the surface contamination limit and the clearance level.
*Research Center for Human and Environmental Sciences, Shinshu University, Matsumoto, Nagano 390‐8621, Japan; †School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113‐0021, Japan; ‡Division for Environment, Health and Safety, The University of Tokyo, Bunkyo, Tokyo 113‐8654, Japan; §Radioisotope Center, The University of Tokyo, Bunkyo, Tokyo 113‐0021, Japan; **School of Science and Technology, Meiji University, Tama, Kawasaki, Kanagawa 214‐8571, Japan.
The authors declare no conflicts of interest.
For correspondence contact: Masahiro Hirota, Shinshu University, Matsumoto, Nagano, Japan, or email at firstname.lastname@example.org.
(Manuscript accepted 18 November 2013)