The main aim of this project was to investigate the impact of making significant changes to the locations of various components in the ceiling of a large cleanroom. Two different scenarios were carefully modelled, designed and simulated by our team and the efficiency of the ventilation system for both scenarios was assessed. In order to determine the ventilation performance in a cleanroom, details of all filters and all inlets/outlets had to be modelled in detail and the assessment on the performance was carried out using a range of innovative metrics including statistical analysis of individual units within the cleanroom, air freshness in different sections and particle tracking. The changes proposed by our team were subsequently implemented in the cleanroom by the client.