44 CFR § 204.21 - Fire management assistance declaration criteria.
(a) Determinations. FEMA will approve declarations for fire management assistance when the Administrator determines that a fire or fire complex on public or private forest land or grassland threatens such destruction as would constitute a major disaster.
(b) Evaluation criteria. FEMA will evaluate the threat posed by a fire or fire complex based on consideration of the following specific criteria:
(1) Threat to lives and improved property, including threats to critical facilities/infrastructure, and critical watershed areas;
(2) Availability of State and local firefighting resources;
(3) High fire danger conditions, as indicated by nationally accepted indices such as the National Fire Danger Ratings System;
(4) Potential major economic impact.