List of natural risk prevention plans of the department of Indre-et-Loire

The Risk Prevention Plans (PPR) were established by the Act of 2 February 1995 on strengthening the protection of the environment. They are the key instrument of the State in the field of risk prevention. Their objective is to monitor development in areas exposed to a major risk.The PPRs are approved by the prefects and generally carried out by the departmental directorates of the territories (DDT). These plans regulate land use or land use through construction prohibitions or requirements on existing or future buildings (constructive provisions, vulnerability reduction work, restrictions on use or agricultural practices, etc.).These plans may be under development (prescribed), implemented in advance or approved.The PPR file contains a presentation note, a regulatory zoning plan and a regulation. Other graphic documents that are useful for understanding the approach (e.g. hazards, issues, etc.) can be attached. Each PPR is identified by a polygon that corresponds to the set of affected municipalities within the scope of the prescription when it is in the prescribed state; and the envelope of restricted areas when it is in the approved state. This geographical table allows mapping existing PPRNs on the department. Each PPRN document existing in the N_DOCUMENT_PPRN geographical table is linked with its GASPAR code in the format “ddd[PREF|DDT|DDTM|DREAL]aaaannnn” (AAAA and NNNN correspond to the reference year and order number of the associated PPR procedure in GASPAR): 1. its administrative procedure for the preparation (or revision) managed in the GASPAR application, on the one hand, 2. its set of numerical spatial constituent data described by the metadata sheet N_PPRN_AAAANNNN (#0001495) on the other hand.风险预防计划（Risk Prevention Plans，简称PPR）由1995年2月2日《加强环境保护法》确立，是国家在风险预防领域的核心治理工具，其目标是对重大风险暴露区域的开发活动开展动态监测。PPR由省长批准，通常由地区领土总局（Departmental Directorates of the Territories，简称DDT）牵头实施。此类计划通过对新建或既有建筑设定施工禁令、提出合规要求（包括施工规范、减灾工程、使用限制或农业作业规范等），实现对土地利用的管控与规范。PPR可处于三种状态：编制中（已下达编制指令）、预实施或已获批。PPR档案包含项目说明文档、管制分区图及配套规制文本，此外可附加有助于理解该计划的其他可视化资料（如风险隐患、核心议题相关图示等）。每份PPR均通过多边形地理要素进行标识：若处于编制指令阶段，该多边形对应指令覆盖范围内的全部受影响市镇；若处于获批阶段，则对应受限区域的边界范围。此地理数据表可用于在省级尺度上绘制现有PPR的空间分布。N_DOCUMENT_PPRN地理数据表中的每份PPRN文档，均与其在GASPAR系统中的编码相关联，编码格式为"ddd[PREF|DDT|DDTM|DREAL]aaaannnn"，其中ddd为行政区域代码，aaaa与nnnn分别对应GASPAR系统中关联PPR流程的参考年份与序号。具体关联逻辑包含两部分：一是其在GASPAR系统中管理的编制（或修订）行政流程，二是由元数据表N_PPRN_AAAANNNN（编号#0001495）所描述的全套空间数值组成数据。