Section § 26502

Explanation

This law requires that the airbrakes on all motor vehicles and vehicle combinations be adjusted and maintained to ensure they can always provide full braking power. Full service brake application means the brake chambers must receive at least 90% of the air pressure left in the reservoirs when the brakes are applied.

The law also allows for special devices or systems that automatically adjust the maximum air pressure to the brake chambers based on the vehicle's load. These systems must not increase the distance it takes for the vehicle to stop and must be safe against failure.

(a)CA Vehicle Code § 26502(a) Airbrakes of every motor vehicle and combination of vehicles shall be so adjusted and maintained as to be capable of providing full service brake application at all times except as provided in subdivision (b) of Section 26311. A full service brake application shall deliver to all brake chambers not less than 90 percent of the air reservoir pressure remaining with the brakes applied.
(b)CA Vehicle Code § 26502(b) The department may by regulation authorize the use of special devices or systems to automatically reduce the maximum air pressure delivered to the brake chambers in order to compensate for load variation and to obtain balanced braking. Permitted systems shall be of the fail safe type and shall not increase the vehicle stopping distance.

Section § 26503

Explanation

This law requires that vehicles with airbrakes, or those designed to use airbrakes on trailers, must have a safety valve that connects directly to the air tank. The valve must be set to open and release air if the pressure goes over 150 psi. It should close slightly above the maximum air pressure limit that is set by the air system's governor. However, the Department may allow for a higher pressure if the vehicle's air system is designed for it.

Every motor vehicle equipped with airbrakes or equipped to operate airbrakes on towed vehicles shall be equipped with a standard type safety valve which shall be installed so as to have an uninterrupted connection with the air reservoir or tank. It shall be adjusted and maintained so that it will open and discharge the air system under any condition at a pressure of not to exceed 150 pounds per square inch and close and reseat itself at a point above the maximum air governor setting. The department may by regulation prescribe a higher maximum opening pressure for air pressure systems designed for, and capable of safely operating with, pressure safety valves with a higher opening pressure.

Section § 26504

Explanation

This law requires that vehicles with airbrakes have their air pressure settings adjusted within specific limits set by the department. These adjustments ensure the brakes operate safely and are based on what the airbrake systems are designed to handle.

The air governor cut-in and cut-out pressures of every motor vehicle equipped with airbrakes or equipped to operate airbrakes on towed vehicles shall be adjusted so that the maximum pressure in the air system and the minimum cut-in pressure shall be within limits prescribed by the department. In adopting regulations specifying such pressures the department shall consider the safe operating capacities of the various airbrake systems which are now or may be used on motor vehicles and shall be guided by the designed capabilities of those systems.

Section § 26505

Explanation

If a vehicle has airbrakes, or is set up to work with airbrakes on trailers, it must have a dependable pressure gauge. This gauge needs to work well, show the air pressure accurately within 10 percent, and be easy to see and read from the driver's seat.

A motor vehicle equipped with airbrakes or equipped to operate airbrakes on towed vehicles shall be equipped with a pressure gauge of reliable and satisfactory construction and maintained in an efficient working condition, accurate within 10 percent of the actual air reservoir pressure, and visible and legible to a person when seated in the driving position.

Section § 26506

Explanation

This law requires that all motor vehicle airbrake systems have a low air pressure warning device. This device must either meet federal safety standards from the time the vehicle was made or follow specific state rules. It should be obvious and easy for the driver to see or hear and needs to give a continuous warning when the air pressure falls below a certain level (between 55 and 75 psi). A simple pressure gauge is not enough to meet this requirement.

(a)CA Vehicle Code § 26506(a) Every motor vehicle airbrake system used to operate the brakes on a motor vehicle or on a towed vehicle shall be equipped with a low air pressure warning device that complies with either the requirements set forth in the Federal Motor Vehicle Safety Standards in effect at the time of manufacture or the requirements of subdivision (b).
(b)CA Vehicle Code § 26506(b) The device shall be readily visible or audible to the driver and shall give a satisfactory continuous warning when the air supply pressure drops below a fixed pressure, which shall be not more than 75 pounds per square inch nor less than 55 pounds per square inch with the engine running. A gauge indicating pressure shall not satisfy this requirement.

Section § 26507

Explanation

This law requires that if a motor vehicle has airbrakes, a check valve needs to be installed and kept in good condition in its air supply system. This valve should be placed either between the air compressor and the first air tank or between the first air tank (called the wet tank) and the second air tank (called the dry tank). Additionally, air for the brakes cannot come from the first tank, and there should only be one pipeline connecting the two tanks.

A check valve shall be installed and properly maintained in the air supply piping of every motor vehicle equipped with airbrakes, either between the air compressor and the first reservoir or tank immediately adjacent to the air intake of said reservoir, or between No. 1 reservoir (wet tank) and No. 2 reservoir (dry tank) immediately adjacent to the air intake of the No. 2 reservoir; provided, that the air supply for the brakes is not drawn from the No. 1 reservoir and that the No. 1 and No. 2 reservoirs are connected by only one pipeline.

Section § 26508

Explanation

If you're driving a vehicle, or a set of vehicles, that use compressed air to apply the brakes, you must have an emergency stopping system just in case the main brake system fails. This law lays out rules for how these systems should work. For instance, you need both a manual and an automatic way to activate the emergency brakes. Cars made before 1964 have a slight pass with some conditions, but they must still have reliable brakes.

Towed vehicles have specific requirements too, like ensuring brakes apply automatically if it detaches. In any vehicle, failure of the main system should still leave you with one working way to stop. If the main brake system fails, you're supposed to only drive far enough to get to a safe spot off the road. There are exceptions, like certain specialized vehicles or those only temporarily traveling through.

Drivers and vehicle owners must know these rules and be able to demonstrate how to use the emergency brakes.

Every vehicle or combination of vehicles using compressed air at the wheels for applying the service brakes shall be equipped with an emergency stopping system meeting the requirements of this section and capable of stopping the vehicle or combination of vehicles in the event of failure in the service brake air system as follows:
(a)CA Vehicle Code § 26508(a) Every motor vehicle operated either singly or in a combination of vehicles and every towed vehicle shall be equipped with an emergency stopping system.
(b)CA Vehicle Code § 26508(b) Motor vehicles used to tow vehicles that use compressed air at the wheels for applying the service brakes shall be equipped with a device or devices with both a manual and automatic means of actuating the emergency stopping system on the towed vehicle as follows:
(1)CA Vehicle Code § 26508(b)(1) The automatic device shall operate automatically in the event of reduction of the service brake air supply of the towing vehicle to a fixed pressure which shall be not lower than 20 pounds per square inch nor higher than 45 pounds per square inch.
(2)CA Vehicle Code § 26508(b)(2) The manual device shall be readily operable by a person seated in the driver’s seat, with its emergency position or method of operation clearly indicated. In no instance may the manual means be so arranged as to permit its use to prevent operation of the automatic means.
(c)CA Vehicle Code § 26508(c) Motor vehicles manufactured prior to 1964 shall be deemed to be in compliance with subdivisions (e) and (f) when equipped with axle-by-axle protected airbrakes using a separate air tank system for each of at least two axles, provided that each system independently meets all other requirements of this section. Each system shall be capable of being manually applied, released, and reapplied from the driver’s seat but shall not be capable of being released from the driver’s seat after any reapplication unless there is available a means which can be applied from the driver’s seat to stop and hold the vehicle or combination of vehicles.
(d)CA Vehicle Code § 26508(d) Towed vehicles shall be deemed to be in compliance with this section when:
(1)CA Vehicle Code § 26508(d)(1) The towed vehicle is equipped with a no-bleed-back relay-emergency valve or equivalent device, so designed that the supply reservoir used to provide air for the brakes is safeguarded against backflow of air from the reservoir through the supply line,
(2)CA Vehicle Code § 26508(d)(2) The brakes are applied automatically and promptly upon breakaway from the towing vehicle and maintain application for at least 15 minutes, and
(3)CA Vehicle Code § 26508(d)(3) The combination of vehicles is capable of stopping within the distance and under the conditions specified in Section 26454.
(e)CA Vehicle Code § 26508(e) If the service brake system and the emergency stopping system are connected in any way, they shall be so constructed that a failure or malfunction in any one part of either system, including brake chamber diaphragm failure but not including failure in the drums, brake shoes, or other mechanical parts of the wheel brake assemblies, shall not leave the vehicle without one operative stopping system capable of complying with the performance requirements in Section 26454.
(f)CA Vehicle Code § 26508(f) Every emergency stopping system shall be designed so that it is capable of being manually applied, released, and reapplied by a person seated in the driver’s seat. The system shall be designed so that it cannot be released from the driver’s seat after any reapplication unless immediate further application can be made from the driver’s seat to stop and hold the vehicle or combination of vehicles. The emergency stopping system may also be applied automatically.
(g)CA Vehicle Code § 26508(g) A vehicle or combination of vehicles upon failure of the service brake air system shall not be driven on a highway under its own power except to the extent necessary to move the vehicles off the roadway to the nearest place of safety.
(h)CA Vehicle Code § 26508(h) A vehicle or combination of vehicles shall not be equipped with an emergency stopping system that creates a hazard on the highway, or increases the service brake stopping distance of a vehicle or combination of vehicles, or interferes in any way with the application of the service brakes on any vehicle or combination of vehicles.
(i)CA Vehicle Code § 26508(i) Any energy-storing device which is a part of the emergency stopping system shall be designed so that it is recharged or reset from the course of compressed air or other energy produced by the vehicle, except that energy to release the emergency stopping system may be produced by the driver’s muscular effort from the driver’s seat. A device shall not be used that can be set to prevent automatic delivery of air to protected air supply reservoirs of motor vehicle emergency stopping systems when air is available in the service brake air supply system.
(j)CA Vehicle Code § 26508(j) Any vehicle manufactured on or after January 1, 1964, which uses axle-by-axle protected airbrakes as the emergency stopping system shall use a separate air tank system for each axle, except that motor vehicles equipped with a dual or tandem treadle valve system need have no more than two protected air tanks in such system, one for each valve.
(k)CA Vehicle Code § 26508(k) This section does not apply to any of the following:
(1)CA Vehicle Code § 26508(k)(1) Auxiliary dollies, special mobile equipment, or special construction equipment.
(2)CA Vehicle Code § 26508(k)(2) Motor vehicles which are operated in a driveaway-towaway operation and not registered in this state.
(3)CA Vehicle Code § 26508(k)(3) Disabled vehicles when being towed.
(4)CA Vehicle Code § 26508(k)(4) Vehicles which are operated under a one-trip permit as provided in Section 4003.
(5)CA Vehicle Code § 26508(k)(5) Vehicles which because of unladen width, length, height or weight may not be moved upon the highway without the permit specified in Section 35780.
(l)CA Vehicle Code § 26508(l) Every owner or lessee shall instruct and require that the driver be thoroughly familiar with the requirements of this section. The driver of a vehicle or combination of vehicles required to comply with the requirements of this section shall be able to demonstrate the application and release of the emergency system on the vehicle and each vehicle in the combination.