The issue is considered related to the probability of emergency situation escalation on negative scenarios associated with the human factor. Taking into account the unlimited response time to an emergency situation in the conditions of its localization and liquidation, it is required to consider personnel errors, including in responding to emergency situations from the point of view of reliability of the «man-machine» system.
Along with this, the concept of reliability in this context should reflect both the correctness and the timeliness of response. Based on this, the application of the indicator of the correctness of actions performance per unit of time as a tool for identifying the efficiency of the personnel actions in emergency situations is described in the article. These issues require special attention of the specialists in various fields, as they are at the interface of technical and psychological sciences. Knowing the reliability indicators of a man-machine system, it becomes possible to solve the vital task on calculating the risks of emergency situations. If we consider the issue in the context of the influence of the current functional state of a person on the overall reliability indicator, the task will be reduced to calculating the probability of emergency escalation. The mechanism for calculating the probability of an escalation of emergency related to the influence of the human factor is considered, which is based on the Methodology for determining the influence of a person functional state on making managerial decisions in case of emergency and accidental situations, and data obtained during the experiment conducted with use of this Methodology.