Emergency preparedness is of paramount importance in successful emergency responses at sea. Therefore, emergency drills are regularly conducted to maintain acceptable levels of emergency preparedness. However, it needs to be considered that emergency drill operations themselves include significant risks, and there is no evidence that these risks are appropriately considered when planning emergency drill operations. Human error is one of the main contributors of accidents during emergency drill procedures. The main question posed is how overall risk, including human errors, during an emergency drill can be correctly evaluated. This paper introduces a new hybrid approach based on the Standardised Plant Analysis Risk Human Reliability Analysis (SPAR-H) method with a fuzzy multiple attributive group decision-making method. The method provides a framework for evaluating specific scenarios associated with human errors and identifies contributors that affect human performance. Estimated human errors are utilised to assess human reliability using a new approach based on a system reliability block diagram. The rescue boat drill procedure for a man overboard is selected to illustrate the method. The findings of this research show each human error probability and its contributing factors per task. As a result, overall reliability of 6.06E-01 was obtained for rescue boat drill operation.