Accidents involving chemical tankers are often highly hazardous. The operational status of cargo tanks and loading/unloading systems is critical to the safety of these ships during service. This paper reviews 62 accident cases related to the cargo tanks and loading/unloading systems of chemical tankers occurring between 2003 and 2021. A statistical analysis of the accident causes is conducted from four perspectives: accident type, deadweight tonnage of the involved ship, ship age, and the ship's operational status at the time of the accident. This analysis aims to summarize the conditions under which these accidents occur. Thirty-one typical cases are selected for a more detailed examination. The potential risks leading to these accidents are categorized into human factors and non-human factors. Finally, targeted control measures are proposed, including suggestions for chemical tanker rules and standards, as well as recommendations for the management and operational requirements of shipping companies. These measures are intended to provide technical support for enhancing the safety of chemical tanker transportation.

The structural analysis of the Ro-Ro access demands further investigation due to its complexity and the applicability problems in the requirements of the vehicle deck size of the China Classification Society Rules for Classification of Sea-going Steel Ships. The plate, beam structure and primary supporting members of the Ro-Ro access are studied to establish the descriptive requirements of the vehicle deck plate thickness and the stiffener scantlings by using the theoretical formula derivation and the numerical fitting method. At the same time, the direct calculation requirements for the primary supporting members of the access that meet the unified requirements of the International Association of Classification Societies (IACS) and cover all kinds of loads are formed and then verified through case calculations. The results show that the optimized descriptive requirements and direct calculation requirements have good applicability. This study is of great significance for improving the safety and lightweight level of the Ro-Ro access structure design.