Abstract
1–cm dose equivalent rates at the surface of blocks made of ordinary concrete, iron, stainless steel and aluminum, which were irradiated by secondary particles produced by 30–MeV protons, and 10–MeV, 30–MeV and 1 to 10 GeV electrons, were calculated by the EGS4 code. The results showed that the induced radioactivity of the “clearance concentration” can be easily detected by an NaI(Tl) scintillation survey meter. Conversion factors of surface dose rate to radioactivity were also calculated.
