How can the use of ammonia as a fuel contribute to the decarbonization of the ship traffic? This question is being investigated and advanced in the research project CAMPFIRE. The sub-project “ammonia-powered inland waterway vessels” examines in this regard the legal framework for the admission of inland vessels with ammonia-based engine. The focus is on the requirements for the technical admission of inland vessels, whereby requirements regarding the construction, installation equipment and the hazardous goods law are especially analyzed. The research targets at identifying obstacles for ammonia-powered inland waterway vessels and at formulating specific proposed amendments for further advancement of the legal framework.