It is imperative to acknowledge that any organisational system is inherently associated with a multitude of risks and elements that are intrinsic to its characterisation. However, the vast majority of studies devoted to risk management, in particular risk assessment, in complex organisational systems suggest dealing with risks in isolation, without taking into account their mutual influence and the interrelationship of their components, and resort to summarising local risk assessments. Conversely, disregarding the structural composition of system components during risk assessment can result in an inaccurate evaluation of the risk entity, consequently leading to the implementation of inappropriate management strategies. In this regard, a comprehensive approach to assessing the risk of an organisational system based on its structure is required. In the context of risk interdependencies, the most promising approach for this task is the integrated rating mechanism. The rules for constructing this mechanism allow the tree structure to be manipulated, thereby taking into account the influence of system elements on each other and on the integral risk. However, it should be noted that risk structures rarely represent binary trees. It is important to note that difficulties may arise when using this mechanism in order to justify the choice of a pair of components for aggregation. The present paper puts forward a generalised modification of the classical integrated rating mechanism. The objective of the modification is to formalise the procedure for transitioning from a risk decomposition structure to a binary tree. The proposed algorithm is considered using the example of the risk of an aviation accident.