The quantification of induced activity in the accelerator structures and their decay profiles are required to be studied for planning the maintenance operations and the disposal procedures. This paper studies in detail the yield of radioactivity generated in the common beam dump materials, like copper and tantalum irradiated with proton beams of 10 and 20 MeV and their decay profiles using Fluka Monte Carlo simulations. The neutron yields and ambient dose equivalent rates generated from the target materials are also estimated using Fluka Monte Carlo code and are presented. Few of the estimated neutron ambient dose equivalent rates are experimentally validated.