Los Angeles County Municipal Code § 326.12 Spark arresters required

No person shall use or operate in, upon, or within any wildfire risk area, any tractor, construction equipment, engine, or machinery, or any steam, oil, or gasoline-operated stationary or mobile equipment, from which a spark or fire may originate, unless such equipment is provided with a qualified device or spark arrester installed in or attached to the exhaust pipe which will prevent the escape of fire or sparks. Said qualified device or spark arrester shall meet the requirements of the current version of the United States Forest Service "Standard for Spark Arresters for Internal Combustion Engines" (Standard 5100- 1). For the purpose of this section, any registered motor vehicle operated on a road or highway and which is equipped with a muffler in good condition, as required by the California Vehicle Code, shall be deemed to be in compliance with this section.

Each chimney used in conjunction with any fireplace, barbecue, or incinerator, or any heating appliance in which solid or liquid fuel is used, upon any building, structure, or premises located within any wildfire risk area, shall be maintained with a spark arrester constructed with heavy wire mesh or other noncombustible material with openings not to exceed 1/2 inch (12.7 mm).