CEQA glossary
Fire hazard severity zone (FHSZ)
An FHSZ classifies long-term fire hazard as Moderate, High, or Very High based on physical conditions.
A fire hazard severity zone, or FHSZ, is a Moderate, High, or Very High classification based on physical conditions that shape the likelihood and expected behavior of fire over a 30- to 50-year period.
Why it matters
The FHSZ label identifies a mapped hazard condition and helps a practitioner select the correct SRA or LRA source record. Appendix G also uses responsibility-area and Very High FHSZ location language to frame its wildfire questions.
Hazard is not the same as risk. Hazard describes physical fire conditions. Risk concerns potential damage under existing conditions and can reflect measures such as fuel reduction, defensible space, and ignition-resistant construction.
What it does not establish
An FHSZ does not establish a project’s wildfire risk, whether a project is “near” a mapped area, whether an evacuation plan would be impaired, or how project design and post-fire conditions should be analyzed. For an LRA location, a state recommendation also does not replace verification of the applicable local designation.
Primary source
The Office of the State Fire Marshal explains the classifications and the distinction between fire hazard and wildfire risk. The Appendix G wildfire section shows where the mapped location fact enters the CEQA checklist.
Related terms
- State Responsibility Area (SRA)
- Local Responsibility Area (LRA)
- Very High Fire Hazard Severity Zone (VHFHSZ)
Published 2026-09-10 · Last materially reviewed 2026-09-10