Monte Carlo N-Particle (MCNP) is a software package used for simulating nuclear processes. Lines of code are entered into the program with information on the source and environment. The program can be used to determine shielding effectiveness, calculate dose, and visually depict dose fields. NPO utilizes MCNP to evaluate shielding materials and placement, supplement experimental shielding data, and engineer effect shielding solutions.

Use of MCNP for the simulation of a Dry Cask.
In the case of shielding a Dry Cask, the packaging, the transfer container and the working platform are modeled in a 3D environment. Added to a combination of the Watt fission spectrum and a gamma profile to simulate the spent spent fuel.
Thanks to this modeling, the shielding can be optimized; to be increased where it is most needed, diminished and / or eliminated, where it is not.