Threat-strategy technique - A system safety tool for advanced design

Although definitions of system safety analysis techniques are relatively mature, several innovations were found to provide a significant enhancement to space station safety. There are a finite number of threats to which a project or program can be exposed (in the case of the space station, a total of 23 were identified). Threats may be grouped as simple or complex according to the physics of their causative factors. Threats may also be grouped as natural, configuration-oriented, and operationally induced. Fire and its causative factors are examined in some detail with proposed countermeasures for each factor. The countermeasures taken to mitigate each threat should be planned early in the development cycle. The aggregate of these countermeasures is termed "the strategy" for each threat. In addition, since solutions or strategies may be simple or complex, based on the causative factors, optimum solutions depend on selecting those strategies that have synergistic properties which minimize the risks associated with the strategy chosen. The strategy for the threat of fire also minimizes the threat of explosion and toxic contamination of the space station atmosphere.