Interpretation ID: nht78-4.9

DATE: 08/31/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: L. F. Henneberger, Esq.

TITLE: FMVSS INTERPRETATION

ATTACHMT: 6/9/78 letter from Lawrence F. Henneberger and Robert W. Green to Joseph J. Levin

TEXT: This is in reply to your letter of June 9, 1978, on behalf of your client, Jacobs Manufacturing Company ("Jacobs" herein).

Jacobs manufactures a diesel engine retarder system which "produces significant deceleration of a large truck so equipped." Jacobs believes that some means should be provided to warn following vehicles when a retarder is in use. It proposes to connect the retarder activation switch to the hazard warning system when a retarder is installed either as original equipment or as an aftermarket accessory. You have asked whether installation of the system would violate either 49 CFR 571.108, Motor Vehicle Safety Standard No. 108, or 15 U.S.C. 1397(a)(2)(A), section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act.

Paragraph S4.1.3 of Motor Vehicle Safety Standard No. 108 prohibits the installation of any device as original equipment that would impair the effectiveness of lighting equipment required by the standard. Paragraph S4.1.1 and Table I require trucks whose overall width is 80 inches or greater to be equipped with a hazard warning flasher system. The Jacobs device may not be installed if it would impair the effectiveness of the required hazard warning flasher system. The intended use of the Jacobs device is that it act as a warning of a decelerating vehicle in the roadway which may present a potential hazard. As such it augments the hazard warning system and, in our view, would tend to enhance rather than impair its effectiveness. Therefore, it may be installed as original equipment without violating S4.1.3. We have no provisions that would either permit or preclude its sale as an aftermarket device, and whether it is permissible as such is a matter to be determined by the laws of the States in which the truck is registered and operated, as well as those administered by the Bureau of Motor Carrier Safety, Federal Highway Administration.

Section 108(a)(2)(A) of the Act prohibits a manufacturer, among others, from rendering inoperative, in whole or in part, any device installed in accordance with a Federal motor vehicle safety standard. Nothing in your letter indicates that the Jacobs device will affect the hazard warning signal flasher's ability to function at times when the Jacobs device is in operation, and therefore, it does not appear that its installation violates section 108(a)(2)(A).

SINCERELY,

Arent, Fox, Kintner, Plotkin & Kahn

June 9, 1978

Joseph J. Levin, Esquire Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Levin:

Our client, Jacobs Manufacturing Company, has manufactured and distributed its well-known diesel engine retarder (the "Jake[R] brake") for a number of years. The Jake[R] brake is sold both in the OEM market as original engine equipment (by such companies as Cummins Engine Co. and Mack Truck, among others) and as an aftermarket installation. This retarder provides auxiliary retarding capabilities independent of the vehicle's foundation brakes and permit a heavy truck to travel at normal traffic speeds on long downgrades, under full control, as well as extending the service life of the foundation brakes.

In recent years, the retarding force generated by current-design engine retarders has increased considerably, and electric driveline retarders with markedly greater retarding horsepower have become available. For example, Jacobs is now marketing an electric retarder (the "Jake ER[R]"), rated at some two to three times the retarding force of a typical large diesel engine equipped with the Jake[R] brake.

Because retarding forces of this magnitude are capable of producing significant deceleration of a large truck so equipped, Jacobs believes that some means should be provided to warn following vehicles when a retarder is in use. In addition, since a truck tractor equipped with a retarder may be used to pull a variety of different semi-trailers, the warning system must utilize existing vehicle equipment and operate both on the tractor alone ("bob-tail" configuration) and with any semi-trailer that may be hooked up.

After careful analysis and based upon a meeting with NHTSA and BMCS representatives on June 6, 1978, Jacobs has concluded that use of the existing hazard warning flasher system would best provide such warning to following drivers. Many states now require trucks moving less than 40 m.p.h. on limited access highways to use their hazard warning flashers to alert other motorists that they are slow-moving.

In order to provide this retarder warning signal automatically, Jacobs proposes to connect the retarder activation switch to the hazard warning system when a retarder is installed, either at the OEM or aftermarket level. Accordingly, the Company requests an advisory opinion that such use and connection of the hazard warning system is permissive and will not violate the requirements of FMVSS 108, nor will it violate the "antitampering" provisions set out in section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act of 1966, as amended.

Lawrence F. Henneberger

Robert W. Green

cc: Z. TAYLOR VINSON; GERALD M. BLOOM; JOSEPH WALSH; ROBERT BRENNER