A surfacic challenge of the PPRN field movements of the valley of the Clain department of Vienna

In general, the stakes are people, property, activities, cultural or environmental heritage elements, threatened by a hazard and likely to be affected or damaged by it. The sensitivity of an issue to a hazard is called “vulnerability”.
This object class includes all the issues that were taken into account in the PPR study. An issue is a dated object whose consideration depends on the object of the PPR and its vulnerability to the hazards studied. A PPR issue can therefore be taken into account (or not) depending on the type(s) of hazard addressed.
These elements constitute the basis of knowledge of land use necessary for the development of the RPP, in or near the study area, at the time of the analysis of the issues.

The issues data represent a photograph (fixed and non-exhaustive) of the assets and persons exposed to hazards at the time of the development of the risk prevention plan. These data are not updated after approval of the RPP. In practice they are no longer used: issues are recalculated as needed with up-to-date data sources.

一般而言，承灾体指受灾害威胁、并可能因此遭受影响或损毁的人员、财产、活动、文化或环境遗产要素。某一对象对灾害的敏感程度被称为“脆弱性（vulnerability）”。
本对象类别涵盖了PPR研究中纳入考量的全部评估对象。此处的“评估对象（issue）”为带时间属性的实体，其是否被纳入考量取决于PPR的研究主题，以及该对象对所研究灾害的脆弱性。因此，PPR相关评估对象是否纳入考量，取决于所应对的灾害类型。
上述要素构成了风险分析阶段，针对研究区域及其周边区域制定RPP（Risk Prevention Plan，风险预防计划）所需的土地利用认知基础。
该评估对象数据呈现了风险预防计划制定阶段，暴露于灾害中的资产与人员的快照（固定且非穷尽）。此类数据在RPP获批后不再更新。实际应用中已不再直接沿用此类数据：需根据需求结合最新数据源重新计算评估对象。