D.C. Mun. Regs. r. 18-720
Each motor vehicle, trailer, semi-trailer and pole trailer, and any combination of such vehicles operated upon a street or highway shall be equipped with brakes in compliance with the requirements of § 720 through 725.
Each vehicle and combination of vehicles, except special mobile equipment as defined in this title, shall be equipped with service brakes complying with the performance requirements of this section and adequate to control the movement of and to stop and hold the vehicle under all conditions of loadings and on any grade incident to its operation.
Each vehicle or combination of vehicles, except autocycles, 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 a surface free from snow, ice, or loose material.
Parking brakes shall be capable of being applied in conformance with the requirements of § 720.3 by the driver's muscular effort, by spring action, or by equivalent means.
The operation of parking brakes may be assisted by the service brakes or other source of power; Provided, that failure of the service brake activation system or other power assisting mechanism will not prevent the parking brakes from being applied in conformance with the requirements of this section.
Parking brakes shall be so designed that when once applied they remain applied with the required effectiveness, despite exhaustion of energy or leakage of any kind.
The same brake drums, brake shoes, 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 parking brakes.
If the means of applying the parking brakes and 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.
Each vehicle shall be equipped with brakes acting on all wheels except the following vehicles:
Each motor vehicle, trailer, semi-trailer and pole trailer, and every combination of such vehicles equipped with brakes, except motorcycles and motorized bicycles, shall have the braking system so arranged that one control device can be used to operate all service brakes.
The requirement cited under § 720.10 does not prohibit vehicles from being equipped with an additional control device to be used to operate brakes on a towed vehicle, and the requirement does not apply to driveway or towaway operations unless the brakes on the individual vehicles are designed to be operated by a single control on the towing vehicle.
All brakes shall be maintained in good working order and shall be so adjusted to operate as equally as practicable with respect to the wheels on opposite sides of the vehicle.
The Director is authorized to require an inspection of the braking system on any motorized bicycle and to disapprove any braking system on a vehicle which he or she finds will not comply with the performance ability standard set forth in § 724 or which, in his or her opinion, is equipped with a braking system that is not so designed or constructed as to ensure reasonable and reliable performance in actual use.
The Director may refuse to register or may suspend or revoke the registration of any vehicle referred to in this section when he or she determines that the braking system on the vehicle does not comply with the provisions of §§ 720 through 725.
No person shall operate on any street or highway any vehicle referred to in this section if the Director has disapproved the braking system upon the vehicle.
Each horse-drawn vehicle engaged in carrying loads on the streets and highways of the District shall be equipped with an effective brake.
The brake on a horse-drawn vehicle shall be deemed effective when that brake will hold the vehicle on any grade which the vehicle can ascend with a full load.
D.C. Mun. Regs. r. 18-720