Alabama Administrative Code › Title 760 - ALABAMA LAW ENFORCEMENT AGENCY › Chapter 760-X-1 - PROMULGATED RULES › Section 760-X-1-.09 - Defining The Adequacy Of Brakes, And Prescribing The Performance Standards Thereof, Of Motor Vehicles Using The Highways Of The State Of Alabama

Current through Register Vol. 42, No. 9, June 28, 2024
(1) Brake Equipment
			 Required Every motor vehicle, trailer, and pole trailer, and any combination of
			 such vehicles operating upon a highway within this state shall be equipped with
			 brakes in compliance with the requirements of this section.
(a) Service Brakes Adequacy Every such motor
			 vehicle and combination of vehicles shall be equipped with service brakes
			 complying with the performance requirements of this rule and adequate to
			 control the movement of and to stop and hold such vehicle under all conditions
			 of loading, and on any grade incident to its operation.
(b) Service Brakes Adequacy Every such
			 vehicle and combination of vehicles except motorcycles and motor driven cycles,
			 shall be equipped with parking brakes adequate to hold the vehicle on any grade
			 on which it is operated, under all conditions of loading on any surface free
			 from snow, ice, or loose material. The parking brakes shall be capable of being
			 applied in conformance with the foregoing requirements by the driver's muscular
			 effort or by spring action or by equivalent means. Their operation may be
			 assisted by the service brakes or other source of power provided that failure
			 of the service brake actuation system or other power assisting mechanism will
			 not prevent the parking brakes from being applied in conformance with the
			 foregoing requirements. The parking brakes shall be so designed that when once
			 applied they shall remain applied with the required effectiveness despite
			 exhaustion of any source or energy or leakage of any kind. The same brake
			 drums, brake shoes and lining assemblies, brake shoe anchors and mechanical
			 brake shoe actuation mechanism normally associated with the wheel brake
			 assemblies may be used for both the service brakes and the parking brakes. If
			 the means of applying the parking brakes and the service brakes are connected
			 in any way, they shall be so constructed that failure of any one part shall not
			 leave the vehicle without operative brakes.
(c) Brakes on all Wheels Every vehicle shall
			 be equipped with brakes acting on all wheels except:
1. Trailers, Semi-Trailers, or Pole Trailers
			 of a gross weight not exceeding 3,000 pounds, provided that:
(i) The total weight on and including the
			 wheels of the trailer or trailers shall not exceed 40 percent of the gross
			 weight of the towing vehicle when connected to the trailer or trailers,
			 and
(ii) The combination of
			 vehicles, consisting of the towing vehicle and its total towed load, is capable
			 of complying with the performance requirements of this rule.
2. Any vehicle being towed in
			 driveaway or towaway operations provided the combination of vehicles is capable
			 of complying with the performance requirements of this rule.
3. Trucks and trucktractors having three or
			 more axles need not have brakes on the front wheels, except that when such
			 vehicles are equipped with at least two steerable axles, the wheels of one
			 steerable axle need not have brakes. However, such trucks and trucktractors
			 must be capable of complying with the performance requirements of this
			 rule.
4. The wheel of a sidecar
			 attached to a motor cycle or to a motordriven cycle or the front wheel of a
			 motordriven cycle need not be equipped with brakes, provided that such
			 motorcycle or motordriven cycle is capable of complying with the performance
			 requirements of this rule.
(d) Automatic Trailer Brake Application Upon
			 Breakaway. Every trailer, semitrailer, and pole trailer equipped with air or
			 vacuum actuated brakes and every trailer, semitrailer, and pole trailer with a
			 gross weight in excess of 3,000 pounds, manufactured or assembled after January
			 1, 1972, shall be equipped with brakes acting on all wheels and of such
			 character as to be applied automatically and promptly, and remain applied for
			 at least fifteen minutes, upon breakaway from the towing vehicle.
(e) Tractor Brakes Protected. Every motor
			 vehicle manufactured or assembled after January 1, 1972, and used to tow a
			 trailer, semitrailer or pole trailer equipped with brakes, shall be equipped
			 with means for providing that in case of breakaway of the towed vehicle, the
			 towing vehicle will be capable of being stopped by the use of its service
			 brakes.
(f) Trailer Air Reservoirs
			 Safeguarded. Air brake systems installed on trailers manufactured or assembled
			 after January 1, 1972, shall be so designed that the supply reservoir used to
			 provide air for the brakes shall be safeguarded against backflow of air from
			 the reservoir through the supply line.
(g) Two Means of Emergency Brake Operation.
1. Air Brakes. After January 1, 1972, every
			 towing vehicle manufactured or assembled after that date, when used to tow
			 another vehicle equipped with air controlled brakes, in other than driveaway or
			 towaway operations, shall be equipped with two means for emergency application
			 of the trailer brakes. One of these means shall apply the brakes automatically
			 in the event of a reduction of the towing vehicle air supply to a fixed
			 pressure which shall be not lower than 20 pounds per square inch not higher
			 than 45 pounds per square inch. The other means shall be a manually controlled
			 device for applying and releasing the brakes, readily operable by a person
			 seated in the driving seat, and its emergency position or method of operation
			 shall be clearly indicated. In no instance may the manual means be so arranged
			 as to permit its use to prevent operation of the automatic means. The automatic
			 and the manual means required by this section may be, but are not required to
			 be, separate.
2. Vacuum Brakes.
			 After January 1, 1972, every towing vehicle manufactured or assembled after
			 that date used to tow other vehicles equipped with vacuum brakes, in operations
			 other than driveaway or towaway operations, shall have in addition to the
			 single control device required by subsection (h), a second control device which
			 can be used to operate the brakes on towed vehicles in emergencies. The second
			 control shall be independent of brake air, hydraulic, and other pressure, and
			 independent of other controls, unless the braking system be so arranged that
			 failure of the pressure upon which the second control depends will cause the
			 towed vehicle brakes to be applied automatically. The second control is not
			 required to provide modulated braking.
(h) Single Control to Operate All Brakes.
			 After January 1, 1972, every motor vehicle, trailer, semitrailer and pole
			 trailer, and every combination of such vehicles manufactured or assembled after
			 that date, except motorcycles and motordriven cycles, equipped with brakes
			 shall have the braking system so arranged that one control device can be used
			 to operate all service brakes. This requirement does not prohibit vehicles from
			 being equipped with an additional control device to be used to operate brakes
			 on the towed vehicles. This regulation does not apply to driveaway or towaway
			 operations unless the brakes on the individual vehicles are designed to be
			 operated by a single control on the towing vehicle.
(i) Reservoir Capacity and Check Valve.
1. Air Brakes. Every bus, truck or truck
			 tractor with air operated brakes shall be equipped with a least one reservoir
			 sufficient to insure that, when fully charged to the maximum pressure as
			 regulated by the air compressor governor cutout setting, a full service brake
			 application may be made without lowering such reservoir pressure by more than
			 20 percent. Each reservoir shall be provided with means for readily draining
			 accumulated oil or
2. Vacuum
			 Brakes. After January 1, 1972, every truck with three or more axles equipped
			 with vacuum assistor type brakes and every trucktractor and truck used for
			 towing a vehicle equipped with a reserve capacity or a vacuum reservoir
			 sufficient to insure that, with the reserve capacity or reservoir fully charged
			 and with the engine stopped, a full service brake application may be made
			 without depleting the vacuum supply by more than 40 percent.
3. Reservoir Safeguarded. All motor vehicles,
			 trailers, semitrailers and pole trailers, when equipped with air or vacuum
			 reservoirs or reserve capacity as required by this section, shall have such
			 reservoirs or reserve capacity so safeguarded by a check valve or equivalent
			 device that in the event of failure or leakage in its connection to the source
			 of compressed air or vacuum, the stored air or vacuum shall not be depleted by
			 the leak or failure.
(j)
			 Warning Devices
1. Air Brakes. Every bus,
			 truck or trucktractor using compressed air for the operation of its own brakes
			 or the brakes on any towed vehicle shall be provided with a warning signal,
			 other than a pressure gauge, readily audible or visible to the driver, which
			 will operate at any time the air reservoir pressure of the vehicle is below 50
			 percent of the air compressor governor cutout pressure. In addition, each such
			 vehicle shall be equipped with a pressure gauge visible to the driver, which
			 indicates in pounds per square inch the pressure available for
			 braking.
2. Vacuum Brakes. After
			 January 1, 1972, every truck tractor and truck first put in use to be used for
			 towing a vehicle equipped with vacuum operated brakes and every truck with
			 three or more axles using vacuum in the operation of its brakes, except those
			 in driveaway or towaway operations shall be equipped with a warning signal,
			 other than a gauge indicating vacuum, readily audible or visible to the driver,
			 which will operate at any time the vacuum in the vehicle's supply reservoir or
			 reserve capacity is less than eight inches of mercury.
3. Combination of Warning Devices. When a
			 vehicle required to be equipped with a warning device is equipped with both air
			 and vacuum power for the operation of its own brakes or the brakes on a towed
			 vehicle, the warning devices may be, but are not required to be, combined into
			 a single device which will serve both purposes. A gauge or gauges indicating
			 pressure or vacuum shall not be deemed to be an adequate means of satisfying
			 this requirement.