This work is based on a numerical study of particle transport and diffusion using ITER parameters. In particular, the effects of introducing a nonmonotonic safety factor (NMSF) in the case of a reversed magnetic shear are shown. These results are compared with those found by using a monotonic safety factor (MSF). Double internal transport barriers are detected influencing the transport and diffusion of particles. The choices of the mode (m, n) and the m/n values play a dominant role for the particle diffusion, which leads to an improvement of the magnetic confinement.