A shield for absorbing radiation emitted by a target during operation of a cyclotron. The shield includes an inner box structure having a recess for receiving the target. In addition, the shield includes a first plurality of shield elements arranged in a layered configuration about the inner box structure. The shield also includes an outer box structure for receiving the inner box structure and the first plurality of shield elements. Further, a second plurality of shield elements is arranged in a layered configuration about the outer box structure. The shield elements are arranged in both horizontal and vertical orientations and are removable.