The planning, construction, maintenance, education, and management elements for the protection of life and property from wildfire shall meet the requirements of this chapter and NFPA 1144.
In cases in which the local jurisdiction declares that an area within the jurisdiction is a wildland urban interface as determined by an assessment tool based upon accepted fire services practices, or where new structures will be located in a wildland/urban interface or intermix area, the AHJ shall perform, or cause to be performed, a wildland fire hazard assessment of each structure ignition zone in the development to determine relative risk, the extent of wildland fire hazard, and applicable mitigation measures.
The structure assessment shall, at a minimum, include the following:
- Identification and documentation of the wildland fire hazards in the ignition zone(s) for each structure within wildland fire hazard areas, according to the elements and conditions in 17.1.4
- Determination of mitigation measures for vegetation, other combustibles, and the structure, including the periodic maintenance associated with such measures
- Establishment of priorities relative to mitigating the risks from wildland fire
- Evaluation of the site for conflagration hazards associated with the property to provide information for fire operations strategies should the site or surrounding properties become involved with fire.
[1144:4.1.2]
The wildland fire hazard assessment shall be the basis for recommended mitigation measures relative to the vegetation, other combustibles, and structures on the site. [1144:4.1.3]
The structure assessment shall document the location of the structure in relation to predominant topographical features, such as flat open areas, ridges, saddles, steep slopes, natural chimneys like steep narrow draws, or small canyons, that will increase the ignition potential of the structure. [1144:4.2.1.1]
The structure assessment shall document local weather conditions, including wind, relative humidity, temperature, and fine fuel moisture content. [1144:4.2.1.2]
The structure assessment shall document nearby structures using the same criteria as the primary structure. [1144:4.2.1.3]
The structure assessment shall document any neighboring properties that could impact the ignition zone of the property being assessed. [1144:4.2.1.4]
The structure assessment shall document the structure's location on the slope relative to the structure's potential exposure to heat from a wildland fire. [1144:4.2.1.5]
The structure assessment shall document all skylights in roof assemblies. [1144:4.2.2.3]
The structure assessment shall document the potential of roof gutters and areas where exterior walls meet roof or deck surfaces to collect litter on surfaces or in crevices. [1144:4.2.2.4]
The structure assessment shall document the construction materials of gutters, downspouts, and connectors. [1144:4.2.2.5]
The structure assessment shall document the materials and construction used in exterior walls and exterior siding. [1144:4.2.3.1]
The structure assessment shall document the materials used for gutter downspouts and connectors on exterior walls. [1144:4.2.3.2]
The structure assessment shall document the materials used in windows and other openings in vertical surfaces. [1144:4.2.3.3]
The structure assessment shall document the location, size, and screening of ventilation openings. [1144:4.2.3.4]
The structure assessment shall document all attached accessory structures as part of the primary structure. [1144:4.2.3.5]
The structure assessment shall document areas next to or under a structure where combustible materials that present a source of flame exposure to the structure might collect. [1144:4.2.3.6]
The structure assessment shall document all vegetative fuels and other combustible materials adjacent to and within 30 ft (9 m) of the structure for their potential to contribute to the intensity and spread of wildland fire. [1144:4.2.4.1]
The structure assessment shall document the presence and location of all heat and flame sources within 30 ft (9 m) of the primary structure. [1144:4.2.4.2]
The structure assessment shall document all projections attached to the primary structure. [1144:4.2.4.3]
The structure assessment shall document detached structures within 30 ft (9 m) of the primary structure that might be ignited by flames, radiant heat, or firebrands from wildland fires. [1144:4.2.4.4]
The structure assessment shall document vehicle parking areas within 30 ft (9 m) of any surface of the structure. [1144:4.2.4.5]
The structure assessment shall document vegetation within the area between the outer edge of the immediate landscaped area and the extent of the structure ignition zone as potential fuel that can convey the fire to the structure. [1144:4.2.5.1]
The structure assessment shall document the species and location of trees and the separation of tree crowns within the area between the outer edge of the immediate landscaped area and the extent of the structure ignition zone. [1144:4.2.5.2]
The structure assessment shall document the presence and location of all heat and flame sources within the area between the outer edge of the immediate landscaped area and the extent of the structure ignition zone. [1144:4.2.5.3]
The structure assessment shall document detached structures within the area between the outer edge of the immediate landscaped area and the extent of the structure ignition zone that might be ignited by flames, radiant heat, or firebrands from wildland fires. [1144:4.2.5.4]
The structure assessment shall document vehicle parking areas within the area between the outer edges of the immediate landscaped area and the extent of the structure ignition zone. [1144:4.2.5.5]
The structure assessment shall document all projections attached to the primary structure that extend beyond the immediate landscaped area. [1144:4.2.5.6]
The structure assessment shall document all other factors that can affect the risk of ignition or the spread of wildland fire on improved property within the structure ignition zone, including the risk of structure fires spreading to vegetation. [1144:4.2.5.7]
Any structure that fails to comply with the requirements of Chapter 5 of NFPA 1144 shall be deemed to increase the risk of the spread of wildland fire to improved property and the risk of fires on improved property spreading to wildland fuels. [1144:4.2.5.8]
From the information gathered in each structure assessment, the AHJ shall require or cause to be developed a wildland fire hazard mitigation plan and schedule to address the wildland fire hazards identified in the specific structure ignition zone assessment. [1144:4.3.1]
The AHJ shall work with applicable agencies and organizations to resolve any conflicts between recommended wildland fire hazard mitigation measures and mitigation measures or objectives of other hazards. [1144:4.3.2]
This plan shall include, but not be limited to, the following:
- Specific mitigation recommendations based on the hazard assessment to reduce the ignition potential around and including the structure
- Construction modification or retrofit necessary to reduce the identified hazards as a minimum or to comply with the provisions of Chapter 5 of NFPA 1144
- Fuel modification recommendations as specified in Chapter 6 of NFPA 1144
- A hazard mitigation implementation and maintenance schedule approved by the AHJ
[1144:4.3.3]
The history of wildland fire in the area under assessment shall be considered in determining required hazard mitigation plan. [1144:4.3.4]
From the information gathered in each structure assessment, the AHJ shall require or cause to be developed a wildland fire hazard severity map of each residential development area addressed. [1144:4.3.6]
The map shall include, but not be limited to, the following data elements:
- Lot designations
- Structure locations on each lot
- Locations of wildland fire evacuation centers or safety zones
- Hazard severity for each lot
- Overlapping ignition zones
- Location of fire hydrants, cisterns, or other water sources for fire fighting
[1144:4.3.7]
The AHJ shall require the property owner to develop and comply with the approved wildland fire hazard mitigation plan and schedule according to 17.1.10.1. [1144:4.4.1]
The plans for construction and development within the wildland urban interface shall be submitted to the AHJ for review and approval.
Safeguards to prevent the occurrence of fires and to provide adequate fire protection and mitigation measures in hazardous fire areas shall be provided and maintained in accordance with Section 17.3.
Permits for use of hazardous areas shall not be issued when public safety would be at risk, as determined by the AHJ. (See Section 1.12 for additional requirements for permits.)
The AHJ shall determine and publicly announce when hazardous fire areas shall be closed to entry, and when such areas shall again be opened to entry.
Unauthorized persons shall not be permitted to enter or remain in closed hazardous fire areas.
Approved signs prohibiting entry by unauthorized persons shall be placed on every closed area and access point.
Lighting, igniting, or otherwise setting fire to any smoking material shall be prohibited unless within structures or smoking areas approved by the AHJ. (See Section 10.9 for additional requirements on smoking.)
Tracer bullets and tracer charges shall not be possessed, fired, or caused to be fired into or across hazardous fire areas.
Rockets, model planes, gliders, and balloons powered with an engine, propellant, or other feature liable to start or cause fire shall not be fired or projected into or across hazardous fire areas.
Explosives shall not be possessed, kept, stored, sold, offered for sale, given away, used, discharged, transported, or disposed of within hazardous fire areas except as permitted by the AHJ. (See Chapter 65 for additional guidance.)
Fireworks shall not be used or possessed in hazardous fire areas unless permitted by the AHJ. (See Chapter 65 for additional guidance.)
Lighted and smoldering material used in connection with smoking bees shall not be allowed in or upon hazardous fire areas except as permitted by the AHJ.
Clearance of brush and vegetative growth from electrical transmission and distribution line(s) shall be provided and maintained in accordance with 17.3.5.1.
A combustible-free space around poles and towers shall consist of a clearing of not less than 10 ft (3.05 m) in each direction from the outer circumference of the pole or tower during such periods of time as designated by the AHJ.
At the time of trimming, clearances not less than those established by Table 17.3.5.1.3.1 shall be provided.
Table 17.3.5.1.3.1 Minimum Clearances Between Vegetation and Electrical Lines at Time of Trimming
| Line Voltage | Minimal Radial Clearance from Conductor | |
|---|---|---|
| ft | m | |
| 2400—72,000 | 4 | 1.2 |
| 72,001—110,000 | 6 | 1.8 |
| 110,001—300,000 | 10 | 3.0 |
| 300,001 or more | 15 | 4.6 |
The radial clearances in Table 17.3.5.1.3.1 are minimum clearances that shall be established at time of trimming between the vegetation and the energized conductors and associated live parts.
Clearances not less than those established by Table 17.3.5.1.4 shall be maintained during such periods of time as designated by the AHJ.
Table 17.3.5.1.4 Minimum Clearances Between Vegetation and Electrical Lines to Be Maintained
| Line Voltage | Minimum Clearance | |
|---|---|---|
| in. | mm | |
| 750—35,000 | 6 | 152 |
| 35,001—60,000 | 12 | 305 |
| 60,001—115,000 | 19 | 483 |
| 115,001—230,000 | 30.5 | 775 |
| 230,001—500,000 | 115 | 2920 |
The site-specific clearance achieved, at the time of pruning, shall vary based on species' growth rates, the utility company specific trim cycle, the potential line sway due to wind, line sway due to electrical loading and ambient temperature, and the tree's location in proximity to the high voltage lines.
The AHJ shall establish minimum clearances different than those specified by Table 17.3.5.1.4 when evidence substantiating such other clearances is submitted to the AHJ and approved.
During emergencies, the utility company shall perform the required work to the extent necessary to clear the hazard.
Persons owning, leasing, controlling, operating, or maintaining buildings or structures in, upon, or adjoining hazardous fire areas, and persons owning, leasing, or controlling land adjacent to such buildings or structures, shall maintain an effective defensible space in accordance with 17.3.5.2.1.1 through 17.3.5.2.1.11.5.
Ground fuels, including native vegetation and plants used for landscaping within the defined landscaping zones, shall be treated or removed. [1144:6.2.1]
Vegetation under trees within the fuel modification area shall be maintained at a height that will preclude ground fire from spreading in the tree crown. [1144:6.2.4]
Tree crowns within the structure ignition zone shall be spaced to prevent structure ignition from radiant heat. [1144:6.2.5]
The fuel modification plan shall include a maintenance element identifying and defining the responsibility for continued and periodic maintenance. [1144:6.2.6]
Every fireplace and wood stove chimney and flue shall be provided with an approved spark arrester constructed of a minimum 12-gauge welded wire or woven wire mesh, with openings not exceeding 1/2 in. (12.7 mm). [1144:5.8.1]
Vegetation shall not be allowed within 10 ft (3 m) of a chimney outlet. [1144:5.8.2]
Accessory structures shall be constructed to meet the requirements of Chapter 5 of NFPA 1144 or shall be separated from the main structure by a minimum of 30 ft (9 m). [1144:5.9]
Permanently located mobile and manufactured homes with an open space beneath shall have a skirt of noncombustible materials, exterior fire-retardant-treated wood, or other ignition-resistant material. [1144:5.10.1]
Vehicle parking areas within the immediate landscaped zone shall be maintained free of dry grasses and fine fuels that could be ignited by hot exhaust systems or firebrands. [1144:5.11]
Heat and flame sources that are unprotected or unsupervised shall not be permitted within 30 ft (9 m) of the primary structure. [1144:5.12.1]
Incinerators, outdoor fireplaces, permanent barbecues, and grills shall not be built, installed, or maintained in hazardous fire areas without prior approval of the AHJ. [1144:5.12.2]
Openings in incinerators, outdoor fireplaces, permanent barbecues, and grills shall be provided with an approved spark arrester, screen, or door. [1144:5.12.3]
Propane tanks and other combustible liquids storage shall conform to NFPA 58 and the wildland fire hazard mitigation plan required in 17.1.10. [1144:5.12.4]
Other combustible materials within 30 ft (9 m) of any structure shall be removed or stored in conformance with the wildland fire hazard mitigation plan as approved by the AHJ. [1144:5.12.5]
Where required by the AHJ because of extra hazardous conditions, additional areas shall be maintained to include additional defensible space from buildings or structures, trees adjacent to or overhanging a building shall be maintained free of deadwood, and the roof of a structure shall be free of leaves, needles, or other dead vegetative growth.
Areas within 10 ft (3 m) on each side of portions of highways and private streets shall be cleared of combustible vegetation and other combustible growth. Single specimens of trees, shrubbery, or cultivated ground cover such as green grass, ivy, succulents, or similar plants used as ground covers shall be permitted to be exempt provided that they do not form a means of readily transmitting fire.
The AHJ shall determine that difficult terrain, danger of erosion, or other unusual circumstances could require additional safeguards.
The provisions of 17.3.7 and Section 18.2 shall be used to determine the design, clearances, and provisions for emergency access (ingress and egress).
Unauthorized vehicles shall not be driven upon fire roads or firebreaks. Vehicles shall not be parked in a manner that obstructs the entrance to a fire road or firebreak.
Radio and television aerials, guy wires, and other obstructions shall not be installed or maintained on fire roads or firebreaks unless the vertical clearance is sufficient to allow the movement of fire and emergency apparatus.
Motorcycles, motor scooters, and motor vehicles shall not be operated within hazardous fire areas, except upon clearly established public or private roads.
See Section 10.7 for requirements on tampering with fire safety equipment.
See 4.5.8 for requirements on maintenance.