Safety Versus Survivability

Over the years, people in the defense industry and government have used the terms “system safety” and “survivability” interchangeably. The misunderstanding of these terms has created issues when preparing system safety analysis documents, such as Functional Hazard Assessments (FHA), System Safety Hazard Analysis (SSHA), and Safety Assessment Reports (SAR). In the past, customers have expected that survivability issues will be assessed in these system safety documents. This results in an extensive amount of time to prepare the document and to meet customer expectations. “System safety” is defined as “the design and operational characteristics of a system that minimize the possibilities for accidents or mishaps caused by human error or system failure.” “Survivability” is defined as “the characteristics of a system that prevent fratricide, as well as reduce detectability of the soldier, prevent attack if detected, prevent damage if attacked, minimize medical injury if wounded or otherwise injured, and minimize mental and physical fatigue.” It is clear, though, by these definitions that the two terms are not the same and should not be used interchangeably. This paper will provide indisputable substantiation that system safety and survivability are two distinct domains, and that an assessment of survivability issues is not documented in system safety analyses reports.