1. A. Every motor vehicle, other than a motorcycle or motor-driven cycle, when operated upon a highway shall be equipped with brakes adequate to control the movement of and to stop and hold such vehicle, including two separate means of applying the brakes, each of which means shall be effective to apply the brakes to at least two wheels. If these two separate means of applying the brakes are connected in any way they shall be so constructed that failure of any one part of the operating mechanism shall not leave the motor vehicle without brakes on at least two wheels.
2. B. Every trailer, semitrailer, and pole trailer of a gross weight of three thousand pounds or more when operated upon a highway shall be equipped with brakes adequate to control the movement of and to stop and to hold such vehicle and so designated as to be applied by the driver of the towing motor vehicle from its cab, and said brakes shall be so designed and connected that in case of an accidental breakaway of the towed vehicle the brakes shall be automatically applied.
3. C. Every new motor vehicle, trailer or semitrailer hereafter sold in this state and operated upon the highways shall be equipped with service brakes upon all wheels of every such vehicle, except motorcycles or motor-driven cycles, and semitrailers of less than three thousand (3,000) pounds gross weight, provided that trucks and truck tractors having three or more axles need not have brakes on the front axle, except when such vehicles are equipped with at least two steerable axles, the axles of one such axle need not be equipped with brakes.
4. D. Every singly-driven motor vehicle and every combination of motor vehicles shall be equipped with parking brakes adequate to hold a vehicle or combination on any grade on which it is operated under any condition of loading, on a surface free from snow or ice.
5. E. The brake shoes operating within or upon the drums on the vehicle wheels of any motor vehicle may be used for both service and hand operation.

6. F.

   1. 1. Every full trailer, semitrailer and pole trailer required to be equipped with brakes, except motor vehicles engaged in drive-away, tow-away operations, shall be equipped with brakes of such a character as to be applied automatically and promptly upon break-away from the towing vehicle, and means shall be provided to maintain application of the brakes on the trailer in such a case for at least fifteen (15) minutes. Air brake systems installed on towed vehicles manufactured after September 1, 1961, shall be so designed, by the use of "no-bleed-back" relay-emergency valves or equivalent devices, that the supply reservoir used to provide air for brakes shall be safeguarded against backflow of air from the reservoir through the supply line. After September 1, 1961, every truck or truck tractor, if used to tow a trailer equipped with brakes, shall be equipped with means for providing that in case of break-away of such trailer the service brakes on the towing vehicle will be sufficiently operative to stop the towing vehicle. Every truck or truck tractor equipped with air brakes, the date of manufacture of which is subsequent to September 1, 1961, and every truck or truck tractor equipped with air brakes on and after September 1, 1961, when used to tow another vehicle equipped with full air brakes, in operations other than drive-away or tow-away, shall, in addition to the above, be equipped with two means of activating the emergency features of the trailer brakes. One of these means shall operate automatically in the event of reduction of the towing vehicle air supply to a fixed pressure which shall be not lower than twenty (20) pounds per square inch nor higher than forty-five (45) pounds per square inch. The other means shall be a manually controlled device 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 manual means of application required by this subsection may be, but are not required to be, separate.
   2. 2. Every truck tractor and truck manufactured after September 1, 1961, which is equipped with power brakes, shall have the braking system so arranged that one application valve shall, when applied, operate all the service brakes on the truck tractor and truck or combination thereof. This requirement shall not be construed to prohibit a truck tractor or truck from being equipped with an additional valve to be used to operate the brakes on a trailer or trailers or as provided in paragraph 1 of this subsection. This requirement shall not be applicable to drive-away, tow-away operations unless the brakes on such operations are designed to be operated by a single valve.
   3. 3. Every truck tractor and truck used for towing other vehicles equipped with vacuum brakes, in operations other than drive-away and tow-away on and after September 1, 1961, shall have, in addition to the single control device as provided by paragraph 2 of this subsection to operate all brakes of the combination, a second control device independent of brake air, hydraulic, or other pressure and independent of other controls, which can be used to operate the brakes on the towed vehicles in emergencies. Such second control is not required by this rule to provide modulated or graduated braking.
7. G. Every bus, truck and truck tractor manufactured after September 1, 1961, which is equipped with an air or vacuum brake system, shall be equipped with reserve capacity or a reservoir sufficient to insure a brake application capable of stopping the vehicle within the stopping distance requirements of Section 12-302 of this title in the event the engine stops. No such reserve capacity or reservoir shall be required on single vehicles if the braking system is so designed and installed as to provide for application of the service brakes through hydraulic or mechanical means in event of failure of the air or vacuum system or the source of supply of such systems. In addition, every truck tractor and every truck used for towing other vehicles shall, when equipped with air or vacuum reservoirs as required by this section, and regardless of date of manufacture, have such air or vacuum reservoirs so safeguarded by a check value or equivalent device that in the event of failure or leakage in its connection to the source of compressed air or vacuum the air or vacuum supply in the reservoir shall not be depleted by the leak or failure.
8. H. Every bus, truck and truck tractor equipped with an air brake system, and, on and after September 1, 1961, every truck tractor and every truck used for towing a vehicle required to have brakes, if the brakes are vacuum-operated, shall be provided with either an audible or visible warning signal to indicate readily to the driver any loss or lack of air or vacuum sufficient to prevent the vehicle from being stopped. A gauge indicating pressure or vacuum shall not be deemed to be an adequate means of satisfying this requirement.

Added by Laws 1961, HB 556, p. 403, § 12-301; Amended by Laws 1967, c. 140, § 5, eff. April 27, 1967; Amended by Laws 2001, SB 539, § 9, emerg. eff. July 1, 2001 (superseded document available).