Human Factors Risk Models (HFRM) for aviation and maritime represent an effort to assess the risk involved in implementing novel designs or making modifications to current systems and practices. Specialists should use this tool to comprehend potential risks and gauge how they affect human performance. The risk models are based on the notion of the “Swiss Cheese” model (Reason, 1990). They operate like logical trees representing a series of events: to quantify the risk associated with an event, the models consider numerous layers to avoid the oversimplified notion of single sites of failure.