The γ radiation hazards in the radioactive compartments in nuclear power plants (NPPs) mainly come from three parts: direct radiation from the γ radiation sources arranged in the compartment itself, penetration radiation from the γ radiation sources arranged in the neighboring compartments, and scattering from the holes in the walls of the compartments as a result of the weakening of the radiation shielding effect of the region due to the installation of penetrations. The current mainstream compartment shielding design in the industry couples the first two hazards and does not incorporate hole-scattering radiation, resulting in a certain risk to the radiation safety of the compartment. Based on the Monte Carlo method of modelling and analysis, a quantitative assessment method of the impact of hole scattering that takes into account the state of the holes at different design stages has been proposed to achieve the closed-loop design of compartment radiation shielding.