Assessing evacuation operation performance in harsh environments

This paper addresses the severity of consequences of ineffectively performing evacuation operations of offshore installations in harsh environments. Hazards, particularly fire, smoke, heat, and extreme weather conditions, can harm personnel both directly and indirectly and prevent personnel from performing an evacuation operation successfully. To demonstrate the dependence of consequences on the hazards, this paper uses an event tree (ET) analysis. The event tree analysis maps all possible sequences of events leading to an accident and thus, reflects the level of knowledge about the evacuation operation. The paper uses ET analysis to develop a logical approach to hazards and consequences with the presence of safety functions. Applications of an ET analysis are discussed for two emergency response actions: a) detecting the emergency alarm, and b) moving along the escape route. In a situation where the offshore installation manager (OIM) delays activating the emergency alarm or the alarm system is damaged, personnel may not receive or hear the message. Availability of both primary and alternative escape routes enable personnel to move to a safe area in an escalating event, such as a series of fires and explosions. The paper discusses the ET analysis of hazards and consequences in specifically a qualitative manner. Information from the analysis can be used in a risk assessment of evacuation operations.