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Interpretation ID: nht75-1.17

DATE: 10/15/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Motor Vehicle Inspection

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your May 29, 1975, letter to Mr. Vincent Esposito of the National Highway Traffic Safety Administration (NHTSA), in which you indicate your desire that a "second independent means of stopping be made mandatory" on newly-manufactured motor vehicles.

Federal motor vehicle safety Standard No. 105-75 (49 CFR 571.105-75) becomes effective January 1, 1976, for passenger cars, and it establishes requirements for the service and parking brake systems of these vehicles (copy enclosed). The test procedures for parking brake testing specify that the service brake control be released in testing the parking brake system. This has the practical effect of requiring a separate parking brake similar to that specified by the Iowa law you cited in your letter.

Federal motor vehicle safety Standard No. 121, (49 CFR 571.121) became effective January 1, 1975, for air-braked trailers and March 1, 1975, for air-braked trucks and buses (copy enclosed). It establishes requirements for the service and parking brake systems of these vehicles. Section S5.6.4 of the standard states that "The parking brake control shall be separate from the service brake control."

Section 103(d) of the National Traffic and Motor Vehicle Safety Act of 1966 (15 U.S.C. 1392(d)) provides that no State or political subdivision of a State may promulgate or continue in effect standards applicable to an aspect of motor vehicle or motor vehicle equipment performance which is covered by a Federal motor vehicle safety standard, unless the standards are identical.

As noted, Standard No. 105-75 and Standard No. 121 include requirements for the parking brake control aspect of braking performance. The Federal requirements must be regarded as conclusive with regard to this aspect of performance in order to maintain the uniformity necessary in a Federal regulatory scheme. If States were permitted to impose additional requirements in an area regulated by a Federal safety standard manufacturers would be confronted with an impossible task of compliance. This reasoning formed the basis of a recent decision rendered in a case brought by the Motorcycle Industry Council, Inc. against the State of California in the United States District Court for the Eastern District of California concerning the preemption of a California State requirement that motorcycle headlamps be wired to operate when the engine is running. The Court held that the California requirement is preempted by the Federal Motor Vehicle Safety Standard No. 108 since the NHTSA intended to cover all aspects of performance directly involving motorcycle headlamps.

Therefore, requirements such as those described in your letter would be preempted by Standard No. 105-75 in the case of passenger cars, since the aspect of performance that would be affected is covered by the Federal standard. The same is true for motorcycles, covered by Standard No. 122, Motorcycle Brake Systems, and trucks, buses, and trailers equipped with air brake systems, covered by Standard No. 121.

With regard to trucks, buses, and multipurpose passenger vehicles that are equipped with hydraulic brake systems, the NHTSA is in the process of developing a hydraulic brake standard. I have forwarded a copy of your letter to the NHTSA Office of Crash Avoidance for consideration in developing the standard in this area.

SINCERELY,

May 29, 1975

Vincent J. Estosito, Director Office of Vehicle Safety Research and Development U.S. Department of Transportation National Highway Traffic Safety Administration

A letter from Mr. George W. Crise of Danville, Ohio that was sent to Mr. Robert F. Tyson, Director of Office of Planning and Programming, Des Moines, Iowa has been referred to this office.

It called our attention that the 1975 cars and trucks are being built without a second means of stopping feature as required by the laws of Ohio and other states.

I have enclosed a copy of the Iowa statutes pertaining to brake requirements and brake performance which clearly indicates that the Iowa law specifies two seperate means of applying the brakes. Each of which means shall be affective to apply the brakes to at least two wheels. If these two seperate means of applying the brakes are connected in any way, they shall be so constructed that failure of one part of the operating mechanism shall not leave the motor vehicle without brakes on at least two wheels.

I was not aware that the 1975 model cars and trucks were not equipped with the means to comply with the Iowa statute.

It is our desire that a second independent means of stopping be made mandatory on new motor vehicles.

Lowell E. Schellhase Supervisor Motor Vehicle Inspection

BRAKES

(Illegible Words) Brake requirements.

Every motor vehicle, other than a motorcycle, when operated upon highway shall be equipped with brakes adequate to control the (Illegible Words) of and to stop and hold such vehicle, including two separate (Illegible Word) the brakes, each of which means shall be effective (Illegible Word) the brakes to at least two wheels. If these two separate means applying the brakes are connected in any way, they shall be so (Illegible Word) that failure of any one part of the operating mechanism shall (Illegible Word) the motor vehicle without brakes on at least two wheels.

Every motorcycle, and bicycle with motor attached, when operated a highway shall be equipped with at least one brake, which may be (Illegible Word) by hand or foot.

Every trailer or semitrailer of a gross weight of three thousand (Illegible Word) or more, and every trailer coach or travel trailer of a gross (Illegible Word) of three thousand pounds or more intended for use for human (Illegible Word) shall be equipped with brakes adequate to control the (Illegible Word) and to stop and hold such vehicle, and so designed as to be (Illegible Word) by the driver of the towing motor vehicle from its cab, or with (Illegible Word) brakes, and weight equalizing hitch with a sway control type approved by the commissioner of public safety. Every (Illegible (Illegible Words) travel trailer, or trailer coach of a gross weight of three thousands or more shall be equipped with a separate, auxiliary means (Illegible Word) the brakes on the semitrailer, travel trailer, or trailer from the cab of the towing vehicle. This Act shall apply to all and used travel trailers sold at July 1, 1971 and on all registered (Illegible Word) trailers after December 1, 1973. Trailers or semitrailers with (Illegible Word) or truck tractor need only comply with the brake requirements. Except as otherwise provided in this chapter, every new motor (Illegible Word) trailer, or semitrailer hereafter sold in this state and operated the highways shall be equipped with service brakes upon all wheels every such vehicle with the following exceptions:

Any motorcycle. Any trailer or semitrailer of less than three thousand pounds gross (Illegible Word) need not be equipped with brakes.

Trucks and truck tractors having three or more axles need not brakes on the front wheels, except that such vehicles equipped two or more front axles shall be equipped with brakes on at least of such axles; provided that the service brakes of such vehicle (Illegible Word) with the performance requirements of section 321.431.

Only such brakes on the vehicle or vehicles being towed in a driveaway-towaway operation need be operative as may be necessary be necessary to insure compliance by the combination of vehicles with the performance requirements of section 321.431. The term "driveaway-towaway" operation as used in this subsection means any operation in which any motor vehicle or motor vehicles, new or used, constitute the commodity being transported, when one set or more of wheels of any such motor vehicle or motor vehicles are on the roadway during the course of transportation, whether or not any such motor vehicle furnishes the motive power.

Referred to in sections 321.181, 321.196, 321.210, 321.464, subsection 1

321.431 Performance ability

1. The service brakes upon any motor vehicle or combination of motor vehicles, when upon dry asphalt or concrete pavement surface free from loose material where the grade does not exceed one percent, when traveling twenty miles an hour shall be adequate:

a. To stop such vehicle or vehicles having a gross weight of less than five thousand pounds within a distance of thirty feet.

b. To stop such vehicle or vehicles having a gross weight in excess of five thousand pounds within a distance of forty-five feet.

2. Under the above conditions the hand brake shall be adequate to hold such vehicle or vehicles stationary on any grade upon which operated.

3. Under the above conditions the service brakes upon a motor vehicle equipped with two-wheel brakes only, and when permitted hereunder shall be adequate to stop the vehicle within a distance of forty-five feet and the hand brake adequate to stop the vehicle within a distance of fifty-five feet.

4. All braking distances specified in this section shall apply to all vehicles mentioned, whether such vehicles are not loaded or are loaded to the maximum capacity permitted under this chapter.

5. All brakes shall be maintained in good working order and shall be so adjusted as to operate as equally as practicable with respect to the wheels on opposite sides of the vehicle.

(Illegible Words)

MISCELLANEOUS EQUIPMENT

321.432 Horns and warning devices. Every motor vehicle when operated upon a highway shall be equipped with a horn in good working order and capable of emitting sound audible under normal conditions from a distance of not less than two hundred feet, but no horn or other warning device shall emit an unreasonably loud or harsh sound or a whistle. The driver of a motor vehicle shall when reasonably necessary to insure safe operation give audible warning with his horn but shall not otherwise use such horn when upon a highway.