Cal. Veh. Code § 35002

(a)
1. (1) This division does not apply to an authorized emergency vehicle owned or operated by a governmental agency while being used in responding to and returning from emergency fire calls, while being moved from place to place in anticipation of emergency fire calls, when used during training in any fire service application or during fire prevention activities, or when vehicles ordinarily used for those purposes are necessarily transported for vehicle maintenance, repair, or service. This subdivision only applies to vehicles purchased prior to January 1, 1994. Vehicles purchased on January 1, 1992, to and including December 31, 1993, shall meet the applicable requirements of Standards 1901 to 1904, inclusive, of the National Fire Protection Association, as those standards were in effect on December 31, 1991.
2. (2) All vehicles described in paragraph (1) first purchased on or after January 1, 1994, shall comply with the applicable permit requirements adopted by the Department of Transportation.
3. (3) For purposes of this section, “purchased” means the date that the operating agency enters into a contract to purchase the vehicle.

(b) All vehicles described in subdivision (a) purchased on or after January 1, 1994, shall meet the following requirements:

(1) It shall be the responsibility of the manufacturer to provide a gross axle weight rating (GAWR), gross combined weight rating (GCWR), and gross vehicle weight rating (GVWR), adequate to carry a full water tank with the allowance for personnel and miscellaneous equipment, including hose load, shown in the table below:

	Personnel	Misc. Equipment
Pumpers	1,200 lbs.	2,000 lbs.
Light attack apparatus	600 lbs.	900 lbs.
Water towers	1,200 lbs.	1,500 lbs.
Aerial platforms with ground ladders	1,200 lbs.	2,500 lbs.
Aerial ladders with ground ladders	1,200 lbs.	2,500 lbs.

Fire apparatus shall be weighed and certified by the manufacturer to determine compliance with the table above prior to acceptance by the purchaser. Apparatus and chassis manufacturers shall furnish certification of the gross vehicle weight rating (GVWR), gross combined weight rating (GCWR), and gross axle weight rating (GAWR) on a nameplate affixed to the apparatus.

(2) A fire apparatus exceeding 31,000 pounds gross vehicle weight rating (GVWR) shall be equipped with a retarder.
(3) For purposes of this section, a “fire apparatus” is a vehicle designed, maintained, and used under emergency conditions to transport personnel and equipment, or for the suppression of fires or mitigation of other hazardous situations, consistent with the 2009 edition of Standard 1901 of the National Fire Protection Association.
(4) Notwithstanding the weight exemption provided for in Chapter 7 of Division 2 of Title 21 of the California Code of Regulations, effective on July 2, 2010, nor any other provision of law, a fire apparatus vehicle is prohibited from towing or hauling any other vehicle or equipment while operating under an overweight permit.
(5) This chapter and Chapter 7 of Division 2 of Title 21 of the California Code of Regulations do not limit the discretion of the department or a local government to deny an application for an overweight permit on the basis of good cause.

(c) A vehicle owned, operated, or rented by a public agency that is being used in responding to or returning from an emergency, may be operated as required, if a reasonable effort is first made by the agency to obtain verbal permission from an authorized officer or employee of the agency having jurisdiction of the highways used, and, upon termination of the emergency, when the vehicle is returning from the site of the emergency, the public agency either obtains a permit at the location of the emergency or makes a reasonable effort to obtain verbal permission from an authorized officer or employee of the agency having jurisdiction of the highways used, and obtains a written permit for that use pursuant to Section 35780 not later than three days after the date of the emergency. As used in this subdivision, “emergency” means a condition that poses an imminent threat of loss of property or a hazard to life, as determined by the public agency charged with responsibility to respond thereto.
(d) A governmental agency operating an authorized emergency vehicle or other vehicle subject to this section is liable to the governmental agency having jurisdiction of a state or county highway for the damage to the highway or a highway structure caused by the operation of the vehicle of a size or weight of vehicle or load exceeding that specified in this division. The cost of repair of the damage is a proper charge against the support fund of the governmental agency operating the oversize or overweight vehicle.
(e) Neither the state nor an agency thereof is liable for damage to a highway or highway structure caused by vehicles operated, pursuant to this section, by or on behalf of a local authority or any other local governmental entity.