The design and the operation of an accelerator imply a series of challenges due to regular and abnormal beam losses, concerning robustness and effectiveness of dedicated intercepting devices (collimators and dumps), failure and damage of delicate components (magnet coils), working conditions of instrumentation (beam loss monitors and various electronics), shielding requirements, and activation-related problems. For these purposes, the calculation of relevant macroscopic quantities, based on the microscopic description of particle physics processes, provides essential pieces of information.
In this seminar, the experience developed in the accelerator sector at CERN with the Monte Carlo code FLUKA will be reviewed, focusing on examples of possible interest for the ESS machine context.