Accident Scenarios for Safety Risk Management of Ammonia Fuelled Ships

Ammonia is deemed to be a promising fuel to reduce carbon emissions from shipping as well as a viable alternative solution as a global hydrogen carrier.Several initiatives are ongoing to demonstrate the use of ammonia in fuel cells and internal combustion engines for use on offshore vessels.While the interest in ammonia increases, so do the concerns regarding its safety.Ammonia is toxic to humans and to marine life, and, at certain concentrations, when mixed with air, could explode if ignited.Although safely transported as a chemical and fertilizer for decades, ammonia has been stored in dedicated carriers.Transfer and handling operations have been performed in this time by highly trained and specialized crews and operators.The potential large-scale implementation of ammonia in the maritime environment and its handling by different users introduce emerging risks and a potential for stricter requirements.This work presents a bibliographic approach for the definition of accidental scenarios for safety risk management of ammonia fuelled offshore vessels and ammonia carriers.A screening of historical accidental events potentially resulting in ammonia released is performed and a statistical analysis of the causes and consequences of the relevant events is provided to support a tailored and effective risk management.