ISO/TR 12489:2013旨在弥合石油、石化和天然气行业安全系统概率计算的现状与应用之间的差距。它为可靠性和安全系统分析员以及石油和天然气行业提供指导。 基本方法（如PHA、HAZID、HAZOP、FMECA）不在ISO/TR 12489:2013的范围内。然而，它们至关重要，因为它们的结果提供了正确实施ISO/TR 12489:2013中描述的方法所必需的输入信息:分析公式、布尔方法（可靠性框图、故障树、事件树等）、马尔可夫图和Petri网。 ISO/TR 12489:2013侧重于随机失效的概率计算，因此，非随机失效- 随机故障不在范围内，即使在某种程度上，随机故障部分包含在现场收集的可靠性数据中。

ISO/TR 12489:2013 aims to close the gap between the state-of-the-art and the application of probabilistic calculations for the safety systems of the petroleum, petrochemical and natural gas industries. It provides guidelines for reliability and safety system analysts and the oil and gas industries. The elementary approaches (e.g. PHA, HAZID, HAZOP, FMECA) are out of the scope of ISO/TR 12489:2013. Yet they are of utmost importance as their results provide the input information essential to properly undertake the implementation of the approaches described in ISO/TR 12489:2013: analytical formulae, Boolean approaches (reliability block diagrams, fault trees, event trees, etc.), Markov graphs and Petri nets. ISO/TR 12489:2013 is focused on probabilistic calculations of random failures and, therefore, the non-random failures are out of the scope even if, to some extent, they are partly included into the reliability data collected from the field.