California Code, Government Code - GOV § 50078.2

(a) The ordinance or resolution shall establish uniform schedules and rates based upon the type of use of property and the risk classification of the structures or other improvements on, or the use of, the property. The risk classification may include, but need not be limited to, the amount of water required for fire suppression on that property, the structure size, type of construction, structure use, and other factors relating to potential fire and panic hazards and the costs of providing the fire suppression by the district to that property. The assessment shall be related to the benefits to the property assessed.

(b) The benefit assessment levies on land devoted primarily to agricultural, timber, or livestock uses, and being used for the commercial production of agricultural, timber, or livestock products, shall be related to the relative risk to the land and its products. The amount of the assessment shall recognize normal husbandry practices that serve to mitigate risk, onsite or proximate water availability, response time, capability of the fire suppression service, and any other factors which reflect the benefit to the land resulting from the fire suppression service provided. A benefit assessment shall not be levied for wildland or watershed fire suppression on land located in a state responsibility area as defined in Section 4102 of the Public Resources Code. This subdivision is not applicable to any benefit assessment levied prior to January 1, 1984, on land devoted primarily to agricultural, timber, or livestock uses.