2025 Fire Hazard Severity Zones SRA

The State Fire Marshal is mandated to classify lands within State Responsibility Areas into Fire Hazard Severity Zones (FHSZ). Fire Hazard Severity Zones fall into one of the following classifications: Moderate High Very High The California laws that require Fire Hazard Severity Zones include California Public Resources Code 4201-4204, California Code of Regulations Title 14, Section 1280 and California Government Code 51175-89. The Fire Hazard Severity Zone (FHSZ) maps are developed using a science-based and field-tested model that assigns a hazard score based on the factors that influence fire likelihood and fire behavior. Many factors are considered such as fire history, existing and potential fuel (natural vegetation), predicted flame length, blowing embers, terrain, and typical fire weather for the area. There are three levels of hazard in the State Responsibility Areas: moderate, high, and very high. Fire Hazard Severity Zone maps evaluate “hazard,” not “risk”. They are like flood zone maps, where lands are described in terms of the probability level of a particular area being inundated by floodwaters, and not specifically prescriptive of impacts. “Hazard” is based on the physical conditions that create a likelihood and expected fire behavior over a 30 to 50-year period without considering mitigation measures such as home hardening, recent wildfire, or fuel reduction efforts. “Risk” is the potential damage a fire can do to the area under existing conditions, accounting for any modifications such as fuel reduction projects, defensible space, and ignition resistant building construction. Click the highlighted text ro review the fire hazard severity zone methodology.州消防局长被授权将州责任区内的土地划分为火灾危险等级区（Fire Hazard Severity Zones，以下简称FHSZ）。火灾危险等级区可分为以下三类：中度、高度、极高。要求划定火灾危险等级区的加利福尼亚州法律法规包括《加利福尼亚州公共资源法典》第4201至4204条、《加利福尼亚州行政法规汇编》第14编第1280节，以及《加利福尼亚州政府法典》第51175至51189条。FHSZ地图采用基于科学原理且经实地验证的模型编制，该模型依据影响火灾发生可能性与火灾行为的各类因素赋予危险分值。考量的因素包括火灾历史、现有与潜在可燃物（天然植被）、预测火焰长度、飞散余烬、地形以及该区域典型火灾天气条件。州责任区内的火灾危险等级分为三级：中度、高度与极高。FHSZ地图评估的是"hazard（危险程度）"，而非"risk（风险程度）"。其与洪水分区地图类似：此类地图依据特定区域遭受洪水淹没的概率等级对土地进行分类，而非具体规定灾害影响。危险程度（hazard）基于能够在30至50年周期内引发火灾可能性与预期火灾行为的物理条件，且不考虑诸如房屋防火加固、近期野火或可燃物削减工程等减灾措施。风险程度（risk）则是指在现有条件下，火灾对该区域可能造成的损害，且会考量所有改造措施，例如可燃物削减工程、防火缓冲带以及耐火建筑结构。点击高亮文本即可查阅火灾危险等级区划方法。